Disadvantages Of A Waterfall Model

Waterfall model:

The Waterfall Model was first Process Model.. It is also called as a linear-sequential life cycle model. It is very simple to understand and use. In a waterfall model, each phase must be completed before the next phase begins. At the end of each phase, a review takes place to determine if the project is on the right path and whether to continue or discard the project and waterfall model phases do not overlap.

Diagram of Waterfall-model:

Advantages of waterfall model:

 Simple and easy to understand and use.

 Easy to manage due to the rigidity of the model and each phase has specific deliverables and a review process.

 Each and every Phase is processed and completed one at a time.

 Works well for smaller projects where requirements are very well understood.

Disadvantages of waterfall model:

 Once an application is in the testing stage, it is very difficult to go back and change something that need to be changed.

 More risk and uncertainty.

 Not a good model for complex and object-oriented projects.

 Poor model for long and ongoing projects.

 Not suitable for the projects where requirements are can be changed in future.

When to use the waterfall model:

 Requirements are very well known, clear and fixed.

 Product definition is stable.

 Technology is understood.

 There are no ambiguous requirements

 The project is short.

Incremental model:

In incremental model the whole requirements are divided into different builds. Multiple development cycles take place here. Cycles are divided up into smaller, more easily managed modules. Each module passes through the requirements, design, implementation and testing phases. A working version of software is produced during the first module.Each sub...

... middle of paper ...

... Spiral model:

Advantages of Spiral model:

 High amount of risk analysis hence, avoidance of Risk is enhanced.

 Good for large and mission-critical projects.

 Strong approval and documentation control.

 Additional Functionality can be added at a later date.

 Software is produced early in the

Disadvantages of Spiral model:

 Can be a costly model to use.

 Risk analysis requires highly specific expertise.

 Project’s success is highly dependent on the risk analysis phase.

 Doesn’t work well for smaller projects.

When to use Spiral model:

 When costs and risk evaluation is important

 For medium to high-risk projects

 Long-term project commitment unwise because of potential changes to economic priorities

 Users are unsure of their needs

 Requirements are complex

 New product line

 Significant changes are expected (research and exploration)