CMMI and Agile are just not comparable

There are oranges, there are apples. What —on the face of the Earth— are you trying to do when asking “Which is better? Oranges or apples?”

A reasonable answer for such kind of questions could be just another question like: “Better for what?” and then trying to figure out what is the core interest behind such apparently illogical questions. Oftentimes, the hidden core interest ends up -once unveiled- a completely different concern with little relation to the original wording.

There is CMMI, for improvement of —whichever selected— process, there is agile mindset that encompasses a concrete development process. So you see, they are different matters and trying to compare each other is futile (CMMI/CMM are related as a whole/part relationship).

As Mark C. Paulk (CMM author) have said* CMM is a prescription of the “what” should an organization do and it is not concerned with any description of how really execute that prescription. An agile process in the trenches represents a description of how development goes on.

*Extreme Programming from a CMM Perspective is your friend, here
ok, here is it