I know it can feel like that sometimes--especially with the shrinkage that comes along with being a type 4. Since I have a somewhat obsessive personality, I decided to limit myself to bimonthly length checks. Much less frustration and disappointment this way.
If you think that you aren't seeing growth because of damage, dryness, or breakage...feel free to post a comment in one of the hair boards. I'm sure you'll get a plethora of helpful tips from some of the naturally curly members. Be sure to include your current hair routine.