The best relationships of this type evolve naturally. A senior engineer on the team mentors a junior one, to help him get more productive. If it’s beneficial for both, it’s okay. But sometimes, people get mentors only because someone wants them to. And it’s not always needed.
The Alpha Geek
The alpha geek is someone who “values intelligence and technical skills above all other traits”. Alpha geeks always make it seem like they have all the right answers. They believe they’re the best ones, undermine the work of their colleagues, and often redo it without any warning.