To have a mentor on your side can make happier your life and can ruin your life as well. I remember at my very fist job, I got a mentor who was an excellent developer, but he was a terrible person. When I made some mistake He become angry and telling me that ''What a fuc* I was thinking about' and 'I should stop developing due to my mental disability' we had very bad conflicts. However this was my only bad experience in mentor ship. My other mentors, current one as well, is very patient and very good teachers not just good developers.