Stars are shown as a relative value to the maximum available at the current level. So if I'm at level 2 and excellent is 25-29, this means the same player would be considered a scout at level 1 and a very good player at level 3.
This is mainly because there's a 9 star limit so in order to increase the skill levels while progressing, the same quality will require higher skill.

just as in real football by the way...