my first paint job

[circa79]

What's good,

I am an artist, and I just finished painting my first pair of uptowns
and it started to crack a little in the front. I prepared it with
Angelus acetone and used Angelus leather paint and finished it off
with none other than the Angelus matte finisher. Any of you pros out
there know why it would still crack.

Your suggestions would be much appreciated

Peace