This points out one of the hardest challenges for me. I'm not a great sales person / negotiator. I'm a geek. When I clock out, I go home and do this same stuff for fun. Managers can see right through this and use it as leverage. Add to the fact I don't have a college degree, and the rest is history. There's a tricky balance between confidence and arrogance and I think its an area I need to improve.