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Agile development is one of the commonly heard terms in recent system development environments.
Although many have heard of the term, they may not fully understand "What exactly is Agile development?" or "What are its advantages and disadvantages?"
In this article, we will explain in detail the characteristics, advantages, and disadvantages of Agile development.
We have also summarized how Agile development works and introduced representative methodologies. This comprehensive guide will be helpful for those considering Agile development.
Supervisor Profile
Akira Shimazoe
CEO of Solashi Japan LLC. Engaged in the development and operation of internal systems at Suntory. Founded Yper Inc., serving as CTO and CPO, contributing to product launch and growth.
What is Agile Development?
Agile development refers to a development method that progresses by repeatedly implementing and testing in small increments.
The word "agile" originally means "quick" or "nimble." Because this method enables rapid system and software development, it is called Agile development.
Here, we will explore the differences between Agile development and the traditional Waterfall development method, along with their appropriate use cases.
Differences Between Agile and Waterfall Development
Waterfall development is a development method where each stage, such as system design, implementation, and testing, is completed sequentially.
The advantage of Waterfall development is that the budget can be easily estimated in advance, and it is easier to plan the assignment of project members.
However, Waterfall development makes it very difficult to add features midway through the process, as it generally does not accommodate changes after the initial planning. This is because all feature requirements and plans must be defined before development begins.
Additionally, the developed system or software is handed over to the client only after the entire project is completed.
On the other hand, Agile development divides the development work into small functional units. The entire process—from requirement definition to design, implementation, testing, and operation—is repeated in small cycles.
Features that have been developed are provided to customers sequentially. Compared to the traditional Waterfall development method, Agile development shortens the development period.
Additionally, the development company and the client company can work together closely, reviewing each feature as they proceed with the development.
Cases Where Agile Development is Suitable
Agile development is suitable for projects where specification changes are likely to occur during development.
Specifically, it is often used in the development of applications, games, and web-related services.
These services are easily influenced by market trends, and it is not uncommon for customer needs to change during development. With Agile development, sudden specification changes or additions and modifications of new features can be handled flexibly.
Additionally, Agile development is also suitable for software that requires an easy-to-use user interface (UI).
To achieve a UI that is easy for users to understand and operate, it is necessary to respond meticulously to various requests from clients.
In other words, in projects where continuous modifications are made in short cycles while listening to user feedback, decision-making methods like Scrum development, which allows for short-term decision-making, are often adopted.
Cases Where Waterfall Development is Suitable
Waterfall development is suitable for projects such as the development of management systems that require precise data recording or the development of banking ATMs.
This method is used when business processes are well-defined, making it relatively easy to list the required features and estimate the necessary workload and timeline.
For projects like management systems and banking ATMs, where system failures must be avoided, the focus is more on high quality rather than rapid releases.
Waterfall development allows for meticulous checks at each stage, enabling the identification and correction of minor errors and bugs throughout the development process.
Furthermore, large-scale projects that require significant resources and time are better suited to Waterfall development.
With Waterfall development, the overall workload of the project can be estimated in advance. This allows for better resource allocation, such as securing a large number of engineers when needed or reducing personnel during specific phases.
The Background of Agile Development
The emergence of Agile development was significantly influenced by changes in the modern business environment. Waterfall development faced two major challenges:
- Traditional development methods could not accurately estimate development time.
- There was a need to respond quickly to customer demands.
Let's explore why Agile development effectively addresses these challenges.
Traditional Development Could Not Accurately Estimate Development Time
In traditional Waterfall development, it was difficult to accurately estimate the time required for development.
Even when an estimated completion time was set in advance, the actual development process often took several times longer. Unexpected bugs and rework frequently caused delays beyond the original projections.
Additionally, as workloads increased, the quality of the developed system or software could decline, leading to missed deadlines and other negative impacts.
This is the background from which Agile development was born. With Agile development, work is carried out in scheduled increments.
This allows for better adjustments in terms of product quality, cost, and deadlines, making project management more efficient.
The Need to Respond Quickly to Customer Demands
In modern business, it is essential to continuously deliver valuable products to customers with a sense of speed.
This also applies to the system development industry. Even if developers create the best possible product, it is meaningless if it does not meet the needs of the client.
Moreover, incorporating user feedback and continuously improving products is crucial for enhancing business value.
Waterfall development often has a cycle of six months to several years from planning to market release, with product releases occurring only once or twice a year. This makes it difficult to respond to customer needs during development.
On the other hand, Agile development allows for regular improvements based on customer feedback, enabling smoother progress while meeting customer demands.
Advantages and Disadvantages of Agile Development
What are the specific advantages and disadvantages of Agile development?
When adopting Agile development, it is essential to maximize its benefits while minimizing its drawbacks.
Here, we will explain the advantages and disadvantages of Agile development in detail.
Advantages of Agile Development
The biggest advantage of Agile development is its ability to smoothly accommodate sudden specification changes.
Agile development assumes from the outset that specifications and designs may change during the process, so it does not rigidly define specifications. This approach allows for fast-paced development.
Even if specification changes occur, Agile development makes it easier to backtrack and reduces the cost of implementing changes.
Additionally, Agile development progresses in small functional units, allowing it to fully respond to customer requests.
Through two-way communication, Agile development enables close collaboration with clients, incorporating their feedback throughout the development process.
Disadvantages of Agile Development
Agile development does not strictly define functionalities or set fixed schedules. Compared to Waterfall development, its direction and objectives may become unclear, which can be a drawback.
Additionally, excessive focus on communication with the client can lead to frequent modifications and added requirements, potentially disrupting the overall consistency of the project.
Furthermore, as development progresses separately within different teams, managing the overall progress of the project can become challenging.
If overall project progress is not well-managed, there is a risk that deadlines may ultimately be missed.
Representative Agile Development Methods
There are various Agile development methods, but the five most representative ones are listed below.
In recent years, businesses have been required to continuously provide valuable products to customers with speed.
This is also true in the system development industry. Even if developers create the best product, it doesn't matter unless it meets the needs of the client.
Furthermore, incorporating the feedback and opinions of users who are using the product and making improvements is crucial to enhancing business value.
On the other hand, the Waterfall development method often takes six months to several years from planning to market release, meaning that products are delivered only once or twice a year. This makes it difficult to respond to customer needs while continuing development work.
In contrast, Agile development allows for regular improvements by incorporating customer feedback, making it easier to respond to customer needs and continue development smoothly.
Advantages and Disadvantages of Agile Development
What are the specific advantages and disadvantages of Agile development?
When adopting Agile development, it's important to maximize its advantages and minimize the disadvantages.
Here, we will explain the advantages and disadvantages of Agile development in detail.
Advantages of Agile Development
The greatest advantage of Agile development is its ability to smoothly respond to sudden specification changes.
Agile development assumes that specification and design changes will happen during the process and does not strictly define specifications upfront. With this assumption, plans are made, allowing development to progress quickly.
If specifications change, it's easy to go back and make adjustments, and the cost of responding to these changes can be minimized.
Additionally, Agile development progresses development in small functional units, allowing for maximum alignment with customer needs, which is also a major benefit.
Agile development emphasizes two-way communication and allows for development to progress while receiving feedback from the client.
Disadvantages of Agile Development
Agile development does not establish strict functional designs or schedules. Compared to Waterfall development, the direction and goals of development are more likely to become unclear, which is a disadvantage.
Furthermore, by emphasizing communication with the client, the development company may continuously respond to modifications or additional requirements, which may result in losing the consistency of the project.
Also, because each team develops different functions, it becomes more difficult to control the overall progress of the development project.
If the overall progress cannot be managed, there is a risk that the project could be delayed.
Typical Agile Development Methods
There are various methods in Agile development, but here are five of the most representative ones.
- Scrum
- Extreme Programming (XP)
- Feature Driven Development (FDD)
- Lean Software Development (LSD)
- Adaptive Software Development (ASD)
Here, we will explain the characteristics and advantages of each development method.
Scrum
Scrum is a method where development cycles, called sprints, last 1 to 4 weeks and are repeated multiple times.
A sprint consists of the following four processes:
- Sprint Planning (determining the development content and how to proceed with the sprint)
- Daily Scrum (a daily meeting during the sprint period)
- Sprint Review (sharing the sprint results and the future direction)
- Retrospective (evaluating and reflecting on the sprint, and considering improvements for the next sprint)
Scrum is team-based, so tasks can be divided among team members, which is a characteristic of this method.
It emphasizes teamwork and communication, making it efficient for progress.
Extreme Programming (XP)
Extreme Programming (XP) is a method where the development progresses while reflecting the client's needs, and detailed plans for the entire project are not made.
XP emphasizes collaboration and communication, with the software's design, development, and testing processes being repeated.
Through repeated iterations of each process, the development direction is determined, making it easy to respond quickly to specification changes.
Additionally, it is easy to incorporate client requests, which improves customer satisfaction.
Feature Driven Development (FDD)
Feature Driven Development (FDD) is a method where development teams are divided based on the user-facing features of the project.
In FDD, the cycle from creating a complete model, planning, designing, and constructing each feature is typically done within 1 to 2 days.
Communication within and outside of the team is primarily done through documentation.
FDD is efficient for fast-paced development, allowing for continuous improvement while creating high-quality systems, and it is well-suited for large-scale projects.
Lean Software Development (LSD)
Lean Software Development (LSD) is a development method that eliminates unnecessary time and tasks in the development process.
It applies the "Lean Production System" used in Toyota's manufacturing to software development.
Lean Software Development focuses on high-quality development by eliminating waste and progresses without a fixed process or methodology. This approach is characterized by its flexibility in how development is carried out.
It emphasizes client feedback and ensures that development progresses quickly, allowing for prompt releases, which is a key benefit.
However, it often requires a lot of feedback, which could lead to an increase in the development and testing processes, potentially resulting in higher costs.
Adaptive Software Development (ASD)
Adaptive Software Development (ASD) is a method that is suitable for complex systems and rapidly changing environments.
ASD follows three cycles: speculation, collaboration, and learning, repeating these processes during the development.
ASD allows flexible development based on changes in customer needs, and since development is conducted after reviews, it helps improve the quality of deliverables.
Basic Steps in Agile Development
The basic steps in Agile development are as follows:
- Formulate a release plan
- Prioritize development tasks
- Repeat iterations and continue developing deliverables
- Determine the completion date of development
Here, we will explain the basic steps of Agile development in more detail.
Formulate a Release Plan
The first step is to formulate a release plan. A release plan refers to the plan for key milestones over the next 3 to 6 months.
Rather than releasing at the end of the plan, multiple releases are typically incorporated within the 3 to 6-month period.
In Agile development, the release plan should summarize the client's requirements while avoiding a strict schedule, making it flexible to accommodate changes.
By setting a schedule with some buffer, it will be easier to respond quickly to specification changes that occur during development.
Determine Priorities for Development Tasks
Next, based on the release plan, the priorities for development tasks are determined. In Agile development, the work progresses by focusing on individual features.
The first step is to list the features to be developed and decide which ones should be prioritized.
However, in Agile development, the priorities of tasks are often reviewed multiple times. Thus, it's common for the order of development to change, or new features may be added.
Typically, it is best to listen to customer requests and feedback before continuing with the development tasks.
Repeat Iterations and Continue Developing Deliverables
Once the priority of the development tasks is determined, the development of deliverables continues through repeated iterations.
An iteration refers to the development cycle where a series of steps are repeated.
Iteration is a fundamental concept in agile development, and by quickly repeating a series of steps, potential issues in the development process can be quickly identified and improved upon.
When following an agile development approach, estimating delivery times and placing orders as with a fixed contract will take time just for the agreement. Therefore, a lab-type contract is the basis.
In agile development, the typical process follows this flow:
- Requirements definition
- Design
- Development
- Testing
First, start with the most important features and continue developing the deliverables through repeated iterations.
Determine the Completion Date of the Development
Agile development ends when both the client and the development company agree on the completion date.
In general, the project ends when the necessary requirements have been fulfilled. Even if all development tasks are finished, if the client feels uncertain about the quality or feels that features are lacking, development will continue.
However, if the client determines that sufficient functionality has been implemented, the project will end at that point.
The project's completion date should be decided through consultation and discussion with the client.
Advantages and Disadvantages of Creating Design Documents in Agile Development
In agile development, speed is emphasized, and documentation such as design documents is often considered unnecessary.
However, in actual agile development environments, the specific rules for design documents and specifications vary by project.
Here, we will explain the advantages and disadvantages of creating design documents in agile development, and when they are needed.
Advantages of Creating Design Documents in Agile Development
The biggest advantage of creating design documents in agile development is that it helps prevent misunderstandings about requirements.
If no design document is prepared, misunderstandings about the requirements are more likely to arise.
Spending time aligning understanding among team members may lead to delays in implementation.
Also, if an engineer leaves for any reason, having a design document allows for proper handover.
If the development team changes in the future or tasks need to be handed over, it is better to have created a design document.
Disadvantages of Creating Design Documents in Agile Development
The disadvantage of creating design documents in agile development is that it takes time to create them.
If one of the team members is tasked with creating a design document, it leads to a loss of speed in the implementation process.
Additionally, once a design document is created, it becomes difficult to change the content flexibly.
In systems that undergo frequent changes in a short period, creating design documents may become obsolete with each release.
The burden on the team members tasked with creating the design document can also impact the overall team progress.
When It Is Better to Create a Design Document in Agile Development
For example, if you are developing a feature that spans multiple systems, it is better to create a design document.
Cross-system processing is complex and requires intricate steps. It is easier to explain using a design document than by describing it verbally.
By using text and diagrams, it becomes easier to align understanding among team members.
Also, if there is a skill gap among team members, creating a design document is recommended.
If an experienced engineer creates the design document and a less experienced engineer follows it, the overall team's development skills will improve.
Achieving Agile Development that Balances Quality and Speed with Solashi
This article discussed agile development, explaining its differences from waterfall development, representative methods, and the process of its implementation.
If you are considering requesting agile development, please contact Solashi Co., Ltd to achieve agile development that balances both quality and speed.
Our company is a system development firm based in Vietnam.
We use web frameworks for rapid prototyping and agile development approaches to achieve development that balances both quality and speed. Even without specifications, we can quickly start development using an agile approach.
Additionally, our engineers are top talents from prestigious universities such as Hanoi University of Science and Technology, Vietnam National University, and University of Trade. We also have Japanese project managers with experience in business startups, providing support and IT consulting services.
If you are considering agile development, feel free to contact Solashi Co., Ltd for inquiries.
Akira Shimazoe
Representative of Solashi Japan LLC. Born in April 1989 in Fukuoka Prefecture. Graduated from the Graduate School of Information and Mathematical Sciences at Osaka Prefecture University. Joined Suntory System Technology Co., Ltd., an IT subsidiary of Suntory Holdings, in 2014. Broadly responsible for the development, operation, and implementation of vending machine delivery management, efficiency improvements, and sales management systems. Founded Yper Inc. in 2017, serving as CTO and CPO. Contributed to the launch and growth of the app-linked delivery bag "OKIPPA." Selected for Toyo Keizai's prestigious "Amazing Venture 100" and Forbes' "Forbes 30 Under 30 Asia 2019."
