V-Model (software Development) - Criticism

Criticism

The V-Model has been criticized by Agile advocates and others as an inadequate model of software development for numerous reasons. Criticisms include:

1. It is too simple to accurately reflect the software development process, and can lead managers into a false sense of security. The V-Model reflects a project management view of software development and fits the needs of project managers, accountants and lawyers rather than software developers or users.
2. Although It is easily understood by novices, that early understanding is useful only if the novice goes on to acquire a deeper understanding of the development process and how the V-Model must be adapted and extended in practice. If practitioners persist with their naive view of the V-Model they will have great difficulty applying it successfully.
3. It is inflexible and encourages a rigid and linear view of software development and has no inherent ability to respond to change.
4. It provides only a slight variant on the waterfall model and is therefore subject to the same criticisms as that model. It provides greater emphasis on testing, and particularly the importance of early test planning. However, a common practical criticism of the V-Model is that it leads to testing being squeezed into tight windows at the end of development when earlier stages have overrun but the implementation date remains fixed.
5. It is consistent with, and therefore implicitly encourages, inefficient and ineffective testing methodologies. It implicitly promotes writing test scripts in advance rather than exploratory testing; it encourages testers to look for what they expect to find, rather than discover what is truly there. It also encourages a rigid link between the equivalent levels of either leg (e.g. user acceptance test plans being derived from user requirements documents), rather than encouraging testers to select the most effective and efficient way to plan and execute testing.
6. It lacks coherence and precision. There is widespread confusion about what exactly the V-Model is. If one boils it down to those elements that most people would agree upon it becomes a trite and unhelpful representation of software development. Disagreement about the merits of the V-Model often reflects a lack of shared understanding of its definition.