During the Ballmer dark ages of Microsoft there was a forced stack-ranking system where managers HAD to give out a certain percentage of good reviews the org, and HAD to give out a preset percentage of bad reviews to the group. In Ballmer's "grand vision" of things, he would constantly cull out the bad performers, and bring in fresh blood. But here's what really happened:
Even if a team was comprised of ALL good people and there weren't any underperformers, 1 in 10 would get a bad review, and 2 in 10 would get a good review - in both cases, regardless if it was deserved or not. If you were the slowest runner, you got culled and eaten by the 10% bear, period. So rather than collaborate with the team for the greater good of Microsoft, people would revert to their inner survival instincts.
"Teamwork" was a nuanced act - folks wouldn't be too helpful to their peers, all the while not being too obvious about it, for fear of being the sacrificial lamb of the bottom 10%. Managers would politic and horse-trade bad reviews. I heard of a story involving 3 managers, who argued over who would get new EmplyeeX, because they knew EmplyeeX was a quiet meek person, who wouldn't object too much if/when given the bad 10% slot during review time.
No one DARED give kudos to their teammates, or any peer within their org for that matter, for fear of moving themselves down the forced stack rank. Imagine a "team" work environment, where no one encouraged one another publicly, and everyone was secretly eager to pull the rug out from underneath their teammates. That was Ballmer's Microsoft. Throw enough parachutes for 9 people on the floor, let 10 people fight for them.
When Satya took over, he knew about the terrible morale and non-teamwork focus Ballmer's cultural legacy had brought to Microsoft - one of the first things he did was push "One Microsoft," a culture of "We're all in this together, lets work together to make Microsoft a successful and competitive company."