I have a question regarding Generic Goals and Practices in the CMMI. In the Staged Representation GG 1 to 3 are Applicable even though the Maturity Level is 5. But in Continuous Representation GG1 to GG5 are applicable to Capability Levels 1 to 5. Why is it like this?
Fortunately, your not the first person to express confusion about this one. The answer is simpler than you might think.
First, a small correction. GG1 is not required for the Staged Representation. Staged appraisals start with GG2. You are correct that GG4/5 do NOT apply to the Staged Representation.
When you approach the CMMI using the continuous representation (one process area at a time is appraised) you need all of the Generic Goals (GG1-GG5) because you are not being appraised on the interdependent aspects of the other Process Areas. In other words, if you being appraised just on Configuration Management (CM), we want to know if you planning it, assigning resources, etc for for Level 2, if your Institutionalizing a defined process (for Level 3), if your managing it quantitatively (for Level 4) and if your optimizing it continuously (Level 5). If you take the Staged approach (a set of PA's at each appraisals) those things in GG4 and GG5 are ALREADY present as process areas (QPM, OPP, CAR, and OID). Also, in ML3, OPD, OPF, and OT help support what is in GG3.
So, given all this, you PROBABLY won't go to Capability Level 4 in OPP and QPM, or Capability Level 5 in OID and CAR because it would be redundant to GG4 and GG5.
Hope this helps!