Development Teams - Can One Bad Apple Spoil the Bunch? [closed]

Question

...One of the most important features a new employee should have is compatibility with the spirit of the people who already work there.
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I am convinced that gaining insight into the developer's real personality is just as important as checking for professional competence, because one bad fit can destroy an entire team.

from Hiring Developers - You're Doing It Wrong

Is this true? And, if so, is it true for managers too?