Waterfall methodology - its purpose and pros and cons

Waterfall methodology describes a specific approach to project management where the stages of development are worked through in a linear matter. This means that each stage of the project has to be finished before the next stage is commenced. The alternative method for the project manager often compared to waterfall, especially for a software development project, is the agile methodology. We have compiled a short guide on what waterfall methodology entails and what its advantages and disadvantages are.

How does waterfall methodology for?

Waterfall methodology comprises of different stages. These differ depending on the details of the project and its sector. The underlying principle of the waterfall model is that each step has to be completed, reviewed, and approved before the project team members can commence work on the next step. Usually, a waterfall project will comprise of the following key stages for a software development life cycle:

Conception

• This is where the initial idea of the project gets developed, a concept is approved, and an assessment that includes a cost/benefit analysis is undertaken

Initiation

• This is where project managers and the team to deliver the project idea will be chosen. This stage also includes defining the scope of the project, including its objectives, deliverables, and purpose

Analysis

• This is where the planned project is reviewed to determine its feasibility and the specifications needed for successful delivery are defined

Design

• All knowledge from the previous stages gets used to determine the project's design specifications so they can be analyzed and evaluated to create a definitive guide to the outcomes and what is needed from the project process to deliver those  

Implementation and coding

• This is where the development team starts the actual coding used in the software

Testing

• Once the previous stage is complete, the software product can be tested to ensure it lives up to the deliverables expected and has no inherent errors

Operation

• This is where the new application is introduced to the real world environment - this stage is not the end of the waterfall methodology, however, feedback from users will feed into the system to identify any additional arising issues and maintenance or tweaks required

Advantages and disadvantages of waterfall methodology

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• The sequential character of this project management methodology makes it easy to use and apply to different projects - the fact that each step is reviewed also gives the project manager a good level of control over errors
• The sequence of each step is clearly defined before commencement of the project - this means that it is easier for a team to share progress and flag up the chance of any deadlines being missed which means that waterfall methodology reduces the risk inherent in any project delivery
• Each stage is reviewed and documented which helps to create a working record of progress - this can subsequently be used as a reference point in the future.

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• Because this approach to project management is so linear, the dependence of each stage on the one before makes it difficult for the project team to respond to spontaneous changes of circumstances or issues
• Because the project team has to complete several stages before the actual execution of a process, there is often a long delay between the initiation of a project and the actual product release

Waterfall vs agile

Agile methodology, on the other hand, follows an iterative approach to development. This means that the steps of a project are broken down into smaller “sprints” (usually last a couple of weeks). Each sprint has a list of deliverables allocated to be prioritized. By the end of each sprint, the progress will be reviewed and evaluated by the project team and possibly the client. This has the advantage of an enhanced role for the end client from the earliest stages, which means they have the helpful ability to suggest changes, and it also improves the speed with which a basic working model can be delivered.

However, this does not mean that all clients are happy with being expected to provide input throughout a project - this also requires high levels of dedication from the teams involved and it can lead to the scope of a project changing throughout delivery.