Why Spiral Model is Better than Waterfall Model?

The spiral model is mainly used in the development processes of complex projects while the Waterfall model is used for simple projects. Both of these models are selected as per the characteristics of the project. The risks during the project are handled by using the Spiral model and it may be considered better than the waterfall model. Also, we will see some differences between the Spiral model and the waterfall model which suggests that the Spiral model is better than the waterfall model.

What is the Spiral Model?

The Spiral model is a software development model that provides an iterative approach to software development. It is based on the idea of a spiral, with each iteration of the spiral representing a complete software development cycle, from customer communication, planning, risk analysis, engineering, construction and release, and customer evaluation.

After each cycle, clients make sure that their requirements are fulfilled or not and if they want any changes then again it passes to the first phase which is customer communication. A risk is any adverse situation that might affect the successful completion of a software project. The most important feature of the spiral model is handling these unknown risks after the project has started. In each phase of the Spiral Model, the features of the product dated and analyzed, and the risks then are identified and are resolved through prototyping.

Spiral model

1. Customer communication: In this phase, customer talks with development team and understand their requirements.
2. Planning: This phase includes overall planning of the software development process.
3. Risk analysis: In this phase, identification of risk in the project is done.
4. Engineering: In the engineering phase, the software is developed based on the requirements gathered in the previous iteration.
5. Construction and release: In this phase, software is built and tested.
6. Customer evaluation: In this phase, development team gets feedback from customer and if they want any changes then development process again starts with the phase of customer communication and if they do not want any changes then project is successfully deployed to the customer.

What is Waterfall Model?

The Waterfall model is a linear, sequential approach towards software development process. It includes phases like software requirements, system design and software design, code generation, testing, deployment and maintenance. It’s like a waterfall because you can only move to the next stage when the previous one is finished. Once a stage is done, making changes to it later in the project is hard.

Waterfall model

1. Requirement Analysis: In this phase, requirements of the customer are gathered and requirement specification document is made.
2. Software Design: In this phase, design of the desired software is made and visualize how the project will be.
3. Implementation/Coding: In this phase, actual coding part is done and final product is ready.
4. Testing: This phase includes testing the software product and checks if the product meets the software requirements or not.
5. Deployment and Maintenance: In this phase, final product is deployed to the customer. While using this software product, if customer needs some changes or customer is facing some issue then this issues can be resolved and changes can be done in the maintenance phase.

Why Spiral Model is Better Than Waterfall Model?

Both Spiral and Waterfall model have their own advantages and disadvantages. The choice between them depends upon the project characteristics, goals and overall nature of project.

1. The Waterfall Model is chosen when the requirements are well-defined and will not change till the project is done.
2. Spiral Model is chosen when requirements of the project will change any time during the software development process and when there is a risk in the project because the Spiral Model handles risks by dealing with them at every stage of development.

Spiral Model vs Waterfall Model

Parameters	Spiral model	Waterfall model
Chosen for	Chosen for the complex projects where requirements are not fixed and may change during the process of development.	Chosen for the simple projects where requirements are fixed .
Approach	Spiral model is an iterative approach towards software development process.	Waterfall model is a linear sequential approach towards software development process.
Feedback	Client can give feedback in the middle of the project.	Client cannot give feedback in the middle of the project.
Changes Done	In Spiral model, changes can be done after each cycle.	In Waterfall mode, changes cannot be done in the middle of the project.
Risks	There are less risks in spiral model.	There are more risks in waterfall model.
Verifying Risks	Spiral model constantly keeps verifying risks throughout the project.	Waterfall model verifies risks mainly at the beginning.
Reusability	Reusability is feasible to a certain extent.	Reusability is not feasible.
Best Suited For	Spiral model is suitable for large projects.	Waterfall model is suitable for small projects.
Progress	In spiral mode, progress can be seen regularly.	In waterfall model, progress can be seen only in final step of the development process.

Conclusion

In conclusion, the Spiral Model is better for projects which needs continuous changes and client involvement. Spiral model is better than waterfall model because it can handle risks during development of the project. There are some more reasons like accommodating changing requirements, continuous feedback, iterative approach,etc. which tells that the Spiral model is better than waterfall model.