When it happens in IT, I am of the belief that it is symptomatic of two problems. Lack of strong technical leadership and substituting process for competence. When IT is not aligned with the business, not delivering value, not managing risk, resources and performance, then we have to do something. We have to change. The people organizing the reorg still seek genuine leadership but have no way of identifying upfront and simply keep iterating until it emerges.
Shops that have long CIO tenure such as Fedex tend to be better aligned because they have strong technical leadership and encourage IT people to make IT better vs focusing on using process as a substitute for competence.