Management noticed that certain software testers were 10 to 20 percent better at finding defects than their peers. By putting these people on the same team, they reasoned, they could form a group that would be 10 or 20 percent more effective and then put the team to work testing the most critical system components.
It didn't turn out that way.
The individuals who made up the team were not exceptionally intelligent or talented, but they all enjoyed testing software and were better than average at it. When these like minded individuals were assembled, they they spent their working hours, lunches and sometimes free time collaborating on how to better find software defects.
Soon the members of team were twice and then dozens of times more effective than their peers, and they began to view their jobs not as testing software, but as breaking software. Team members took a well-deserved pride in their abilities and began to cultivate an image of villainous destroyers. As a group, they began coming to work dressed in black and took to calling themselves "The Black Team."
From The Black Team. (Hat tip to Adam "ata" Atlas and Mike Blume.)