Employees who act like children into their 30s.
I've got this one guy who works for me who internalizes everything. He does not know how to take constructive criticism. To him, everything is a personal attack. We have handled him with kid gloves for the 3 years he has worked with us, because we know he's "sensitive." I'm finding out that we should have been more blunt with him all along. If we ask him to make a change to the way he's doing something, he sulks off to his desk and doesn't talk to anyone for a week (no joke).
Grow up, Drew.
BTW, if anyone is looking for a cleared .NET developer, I will gladly pass along his resume.