"It may not be the most effective, but it is the most common by far. Shaming performance "meetings", stern "talking-to" and threats of poor performance reviews are the standard motivational tools. Bonuses, free pizza and beer on fridays, and the occasional "attaboy" are far and few between, from my experience."
No argument here, that is definitely the most common, despite the fact that I don't think it works.
Also, sometimes someone can play the "asshole" role (strict or no-nonsense project management) without it being a completely negative reinforcement. Someone needs to stay focused on the overall objective and unfortunately has to "crack the whip" once in a while to remind others to stay focused as well.
Granted, it's a fine line. Unfortunately for Linux, Linus is incompetent at that aspect of his job.