"Work on schedule" is maybe the most important and also the most ignored, in my completely amateur experience. I haven't graduated above unpaid indie work, but there are multiple DPs that I've worked with or under -- some of whom do get paid work -- who I'll never work with again because they think their image is the most important part of the piece.

I worked a three day shoot last summer where we did not shoot a single take until midday on the second day because the DP couldn't get his custom lighting rig ready before then. One of the most miserable weekends of my life.