10.9 Software Development Life Cycle (SDLC) Models

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There are lots of SDLC models to choose from. My belief is that the model presented in this book will satisfy almost any type of project whose scope is more than a trivial effort. While some advocate the need to choose a model for a project, I have found that the project is better off adhering to the chosen model. As I stated earlier in this book, the SEP model may not be the only game in town, but it is one of the most venerable. Why would there be reason to deviate from this model? My answer is that there is very little reason for a project leader ever to do so—leave that to the SPMO itself.

Adoption of the SDLC Model, for example, over the SEP process described herein is a matter of choice for an organization’s SPMO leadership to make, not a project leader. I find the two systems so closely aligned that there is really very little difference. There are, of course, other models too. My point is that as long as all of the tasks required in this book are accomplished, by whatever model, the SPMO can select and use the model that best suits its business needs.

10.9.1 How to Identify the Right Model

From an SPMO perspective, selection of the SDLC model should involve a review of the types and scope of projects undertaken. If most projects average $1 million or more in costs, then SEP is appropriate. On the other hand, if most projects cost $25,000, it may be wise to modify the SEP or select another SDLC to suit the scope of effort. This is a business-tailoring process that should not be taken lightly because the costs of choosing the wrong model, or using the SEP to overengineer a process, are very high. The SEP is designed to take small and large projects and tailor them to suit the business need. In some organizations, however, I recognize that SEP may be a drag on resources because the process piece of SEP must be enforced by the SPMO in order to be effective. In organizations where the order of the day is small, nimble projects with small scope, my recommendation is to tailor, at the SPMO level, the SEP to streamline everything that seems to be unnecessary to your specific business. Be careful about trimming indiscriminately, however. Remember, everything you find in the SEP is there for a reason.

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