[Falkon1313]

In some cases, probably. But in others, bringing your knowledge of X into the team that does Y can be quite valuable. Consider the case of a former product manager who knows very well what the customers need from the product, and how they use it, and now also understands the code and dev process - any dev team can really use someone like that. A subject matter expert, someone who knows the industry, designer, or whatever, can bring a lot of value to a different role.