We can look at your example from two sides.
1. Your manager might have a handful of guys who are eager to grow on his
team, and he need to balance it out by hiring someone who is less aggressive
.
2. Its also a good thing for the candidate since he won't be happy after he
joins. If the potential of growing is truly important to him, this is not
the right opportunity.
Personally, I think a capable manager should be able to help his reports to
grow. And usually its easier to motivate people like that than someone who
just doesn't care.