Theoretical processes are perfect for companies that have clearly defined processes or procedures. It is very easy to measure success and control cost with this type of process. On the other hand, the success of managing technical projects can only be measured empirically since Information Technology is protean in nature. In other words, success depends on certain variables that may or may not be in place for the next project. This variable dependency is what makes tracking metrics and measuring success for applications so difficult.
Either of these two process types is great at the functional or departmental level. If a company decides to implement a theoretical process corporate-wide it will begin to notice problems that did not exist before; mainly in the area of software application development. Instead of realizing faster time-to-market and other cost savings, the opposite happens. The department experiences an increase in project costs and missed project deliverables. This is known as the "process trap" and every company that has tried to force an enterprise-wide process onto the IT Department has fallen into it.
Don't let your company become part of that statistic. Just because every other company is doing the same process, does not mean that they are doing it correctly.
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