Agile vs Waterfall Model: Which One Should You Choose

Key takeaways:

1. What are the Agile and Waterfall models in software development?
2. What are the pros and cons of Agile and Waterfall models?

If you can recall our blog on software development models, you already know what Agile and Waterfall models are. Yes, these are the two most widely used software development models. These models specify the various stages of the development process and order in which they need to be carried out. But these aren’t the only two models. There are several other models with different functionalities and objectives. Here are some top-ranked ones are:

1. Agile model
2. Waterfall model
3. V model
4. RAD model
5. Spiral model
6. Iterative model
7. Incremental model
8. Prototype model, etc.

The selection of a model is a crucial step in software development. This is because, based on the model, the testing and development processes are executed. A golden rule states that look at your project requirements and choose accordingly. That’s it. In today’s article, our prime models are Agile and Waterfall. The sole reason for this is that it uses these in over 70% of businesses. An eye-catchy statistic about Agile & Waterfall

What is an Agile Model?

We base the Agile method on an incremental + iterative process where the project requirements change frequently. In this, it uses regular customer feedback for developing better software. While using the Agile model of testing, continuous testing is important at every iteration. Hence, scaling up of products is easy in this. 

Agile model in Software Engineering

“Agile model of operation” refers to an approach to software development focused on iterative development. … Each iteration requires a team going through a complete life cycle of software development, including preparing, evaluating specifications, design, coding, and testing before the client is shown a working product.

What is the Waterfall Model?

The Waterfall model is a contrast to the Agile model. While the Agile model follows an incremental and iterative approach, the waterfall follows a sequential and linear approach. 

Waterfall Model in Software Engineering

The basic software development life cycle model is the classical waterfall model. It is really straightforward but idealistic. This model was very popular before, but it is not used nowadays. It is very significant, however, that all the other life cycle models of software development are based on the classical waterfall model. Hence, because of this, the requirements don’t change once the process gets started. This is both an advantage and disadvantage of this model. In this, it does not use customer feedback at any stage of the development process. Plus, scaling up of projects is difficult in this case. 

Major Advantages of the Agile Method

1. It is a client-focused model. Hence, the client has the major say during the entire development process.
2. The Agile teams are well-balanced and qualified enough to deliver better results.
3. The Agile model ensures that it maintains the standard of quality at each stage.
4. Since it’s incremental and iteration based, the team and client know the exact progress of the project.
5. The entire project completes within the stipulated time limit.
6. The Agile method focuses on the client’s business values.
7. With Agile, the client can estimate the exact costing of the project.

Major Advantages of the Waterfall Model

1. It is a traditional method and thus less complex than the Agile one.
2. The Waterfall model is easier to manage.
3. It ensures faster delivery of the project under a minimum budget.
4. It is most suitable for small projects where requirements are limited.

Major Limitations of the Agile Model

1. The Agile model is only suitable for large projects and not for smaller ones.
2. It requires frequent changes in the requirements and thus, cost predictability is difficult.
3. The overall cost of the implementation is higher than in other models.
4. It is difficult to understand by a newbie.

Major Limitations of the Waterfall Model

1. The Waterfall model is not suitable for large models.
2. All the requirements must be clear in the beginning.
3. It is less effective as compared to other methodologies.
4. Moving back and forth between the phases is difficult.
5. The testing process starts only after the development process is over.

Although both the models have their pros and cons, it is difficult to choose one among them. While the Agile model fits for large projects, the same doesn’t hold in the Waterfall’s case. Hence, project requirements and project size are the two factors to look at while choosing one. 

Also Read: Agile Testing Methodology