This question's about you. See also the accompanying poll, Why don't your friends use Quartz Composer?.
(You may choose more than one response, or write in a response if a problem isn't mentioned.)
Apple hasn't focused on developing QC for several years
79% (60 votes)
QC doesn't support modern graphics (e.g., geometry shaders, shadows)
47% (36 votes)
QC's audio support is too limited
36% (27 votes)
Compositions run only on Mac OS X
34% (26 votes)
QC's editor is too slow when working with large compositions
28% (21 votes)
Apple's QC documentation is inadequate
26% (20 votes)
QC doesn't integrate well with other apps (e.g., Keynote, AE)
24% (18 votes)
QC is unreliable
24% (18 votes)
QC is too slow/inefficient
22% (17 votes)
QC lacks adequate tools for developing user interfaces
21% (16 votes)
The public plugin API is too limited
20% (15 votes)
QC's editor works only on Mac OS X
18% (14 votes)
There aren't enough patches for QC
16% (12 votes)
QC lacks adequate tools for text-based programming
9% (7 votes)
QC can't natively build standalone applications
8% (6 votes)
It's too hard to create plugins for QC
8% (6 votes)
QC's editor is too hard to use
8% (6 votes)
It's too hard to express myself using QC
7% (5 votes)
Total voters: 76