From graduate students and postdocs in the chemical sciences
http://www.ranker.com/list/why-your-labmates-may-dislike-you/gradchem,
You are obsequious and insincere
You are only nice to professors or people you want something from.
You are a mess
You leave bench tops, waste, glassware, and instrumentation (e.g., HPLC, NMR, MassSpec etc.) a mess.
You are rude
You don't respect people's thoughts or space.
You hoard lab equipment/space
You use hours of instrumentation (e.g., NMR) time and are greedy with lab supplies.
You don't give proper credit
You do not acknowledge others that have helped you or you steal ideas
You are arrogant
You condesend to those (i.e. undergrads, graduate students etc.) you are supposed to mentor.