Agile vs. Waterfall: Why They Are not Competitors at All
When starting a new software development project, a client has to select a contractor and an appropriate methodology for the project development.
There is currently no universal technique to building a solution.
So, a reasonable inquiry is:
Which technique should be used, and what problems should be anticipated?
A Quick Intro About Software Development Methodologies
The selection of a methodology for software development is based on 4 key points:
- Business objectives;
- Scope of work;
Choosing the right approach for solution building is highly important. The wrong methodology can negatively affect the whole project. Therefore, before choosing, it is necessary to overview and analyze the peculiarities of each approach.
The most popular approaches today are Waterfall and Agile. Supporters of Agile, just like supporters of Waterfall, claim that their method does deliver better software. However, there's no proof why it is so. They are completely different.
The Waterfall methodology is well-planned and detailed. Agile, on the other hand, means development flexibility and the capacity to make modifications at any stage of the program. The exact opposite.
In this article, we will compare Agile vs. Waterfall and determine the key features of each. Additionally, you’ll learn the advantages and drawbacks of Waterfall and Agile and figure out which software development methodology is suitable for your given project.
What is Waterfall?
A Waterfall model of software development presupposes that all the stages of work are sequential. The next stage starts only after the previous one is completed.
This approach to software development consists of 5 main stages:
The key aspect of the Waterfall approach is that all client’s requirements are collected at the very beginning of the work. This allows for planning each of the subsequent stages and following the plan without significant deviations.
In the design stage, the work falls apart into two sub-stages. First comes the logical stage. It includes the consideration of the solutions. Second, comes the physical stage. The considered solution becomes viable through specific requirements.
This stage implies the direct work of software developers. They implement the solution according to the requirements established in the previous stage.
At this stage, the client checks the solution and makes sure that all the requirements are met. The solution release to the market follows the stage.
5. Maintenance and support
The client uses the solution during this stage. Any shortcomings and bugs that occur go to the development team. The team helps to fix them and updates the solution.
Widely-used Waterfall techniques include:
- Sashimi is one of the most popular Waterfall models. The stages go one after the other. At the same time, they overlap one another. This allows for starting the design stage during the information collecting. This model adds the flexibility that the Waterfall methodology needs.
- Waterfall with subprojects is a Waterfall method that is divided into three distinct phases. 1. Development of a concept; 2. Design; 3. Product structuring. Every one of those sections has different phases of development. They are merged into one another at the end of each step of the process.
- The risk reduction model allows for dividing a big project into smaller ones. It helps to identify gaps before the software product's release.
The essential aspect of Waterfall is that taking a step back or jumping over an iteration is nearly impossible. Only after all of the previous stage's work is done can the transition to the next stage be made. Changes to bug fixes or functionality are made only when the project has been released.
The Waterfall model's work is organized. The conditions and the cost of specific development are established.
What is Agile?
Agile is a software development technique that is built on the idea of adaptable project management. Kanban, Scrum, FDD, Extreme Programming (XP), Lean, and a slew of other methodologies are included in this approach.
The popularity of Agile has always been high. A quick Google Trends query suggests that it is still growing and is not at its peak.
The ability to create a project in multiple cycles is a major aspect of Agile (iterations). At the completion of every iteration, the client sees an interim result and decides on where to move next.
The process of creating a new solution falls into several cycles. Each lasts for about 1 week to 1 month. According to on the parameters of the project, the client and the development team negotiate the timeframes. Every cycle is a mini project finished. It incorporates examination, arranging, testing, and execution stages. As an outcome, the client gets a solution and can adjust it at any time.
The main principles of the Agile methodology are:
- Efficient collaboration is more vital than technologies and processes. The aim is to develop a project of excellence;
- Any necessary changes could be made at any development cycle;
- At the completion of each cycle, the solution is revised;
- It is more vital to be prepared for modifications and changes during the development phase than to stick to the initial plan.
Among the most popular Agile methods are:
Scrum is an Agile program management approach built on the sprint concept. In the course of a week to a month a functioning version of the solution is prepared;
Extreme Programming (XP)
In this technique, Communication with the client is essential at all stages. It becomes easier to identify the defects of the former stages and determine the required effectiveness for the solution;
This approach is centered on the management system of production. The major distinction is that product improvement at all phases of process organizations is continuously improved.
Agile methodology is often seen as universal. The challenge arises in the time limitations for the client and the worry that the initial budget would be exceeded. Communication between the client and the development team is of great importance.
The client may ensure that the project will be original, fascinating, and demonstrated in the tiniest detail by selecting this type.
Agile vs. Waterfall: When is it Best to Use Each Methodology?
Waterfall and Agile software development approaches have their advantages and drawbacks. Each of the methodologies helps to solve certain problems and requires adapting.
What should you keep in mind when selecting a methodology for your project? We suggest considering the following points:
The Waterfall model is a systematic technique for developing software. It provides minimal flexibility since it is difficult to make modifications later. On the other hand, its great level of flexibility is one of the main justifications for choosing the Agile method.
The agile method permits modifications in the needs of the project after the completion of initial planning. The Waterfall model offers no opportunity to change the requirements after the project development process has been started.
At the start of the software development process, the risk agreement is concluded. The whole danger of waterfall is minimized through the project of a fixed cost.
For fixed-cost projects, the Agile approach is not suited. It is ideal for time and material (T&M) or floating funding projects.
3. Development stages
The Agile methodology follows an iterative development model. During the whole software development process, stages such as planning, development, and prototyping occur more than one time.
All stages occur just once throughout the whole process in the Waterfall technique to software development.
The main focus of Waterfall is product creation. The main focus of Agile is meeting the client’s needs and requirements for a product. No matter if the requirements appear during the development process.
5. Detailed product description
With a flexible approach, At any time throughout the software development process, you could alter the project details description.
This does not apply to the Waterfall model. It becomes hardly possible to change project details after project development.
6. Team coordination
The Waterfall method is based on extremely minimal team collaboration or synchronization. In all phases of software development, the project manager is accountable for the final say. Moreover, the interchangeability of team members is not possible.
Instead of this, the Agile approach requires a smaller, but committed team to work. Therefore, the level of cooperation among its members is quite high.
Agile team members are interchangeable. Hence, they are faster. Furthermore, this method does away with the necessity for project managers. The whole team has the responsibility for the software project management.
There is a unique test step in the Waterfall technique. It occurs when the development stage has been completed. Testing goes together with software development under the Agile methodology.
The test plan is rarely revised during the testing stage of the Waterfall model. In contrast, the test plan for an Agile project is revised after each sprint.
When is it Best to Use Waterfall?
The Waterfall is suitable if:
- The requirements of design have been carefully considered and remain unaltered. The buyer understands the product concept;
- Technologies and methods are known ahead of time;
- The solution that has been developed is complicated and costly;
- Product quality is of the first importance. The secondary importance is time and money;
- The client doesn’t idea to take part in the implementation of the project. The project implementation is totally outsourced;
- The contractor software company is ready to take responsibility for the failure to meet the deadlines and budget increases.
When is it Best to Use Agile?
Agile is the right choice when:
- The list of parameters is not yet determined. You plan to introduce changes;
- The project makes use of experienced staff with a high degree of professionalism;
- The client participates actively in the project implementation process;
- At any phase of the project, the client must make changes as soon as possible;
- It is necessary to create a working form of a solution in a short time (MVP);
- It is necessary to develop a solution for a flexible business niche.
Agile vs. Waterfall: Pros and Cons
Both Agile and Waterfall will help you create a software solution. However, you need to select the methodology that will help you to implement your project efficiently.
To make the right choice, it is necessary to remember the benefits and drawbacks of each methodology.
Benefits of Agile
- It is independently possible to make the mandatory modifications and introduce new features. The competing advantages of the finished solution are substantially increased;
- The project is divided into relatively short and clear stages. The client gets a working product at the completion of each stage;
- At any iteration, a flexible adaptation process. It reduces production dangers;
- A fairly quick trial release. It is useful for any further adaptations and testing;
- A high level of participation from all members of the team, as well as regular connection with the client.
Benefits of Waterfall
- Before starting work, the expenses and terms of execution are clear. As a result, the client will understand clearly when the project would be finished and how much money is required;
- Work structure that is intuitive and suitable for both beginners and experienced professionals;
- A Detailed, well-structured plan of work and well-considered documentation;
- Reporting on a regular basis. It is simple to keep track of time and identify dangers throughout project implementation;
- The team's responsibilities are well-defined and do not alter during the whole project.
Drawbacks of Agile
- Calculating the ultimate expenses is nearly difficult. Depending on the project's characteristics, the demands may alter;
- The Agile methodology necessitates a high level of participation and immersion in the process. For less experienced contractors, this might be challenging;
- The prospect of repeated revisions might become a danger of never-ending project improvement;
Drawbacks of Waterfall
- The project's requirements are established at the start and cannot be modified until the job is completed;
- Changes cannot be made throughout the development phase;
- The client would not see the finished product until it is released. Changes will anyway necessitate extra time and funds;
- The Waterfall model evaluates the product after it is released. As a result, issues are discovered only when the product has been introduced.
Conclusion: Why Agile vs. Waterfall are not Competitors?
Agile and Waterfall are different forms of software development methodologies. Hence, each is good in one scenario but impractical in others.
Software development projects with changing requirements are ideal for the Agile methodology. On the contrary, for software development projects with specific requirements, the Waterfall model will be the best choice.
When choosing a methodology, make sure to carefully study the benefits and drawbacks of the approaches. Also, take into account the advice of specialists for determining your set of requirements.