Spoken like a true beaurocrat who only cares about the individual KPIs. If all you look at is the individual, you'll miss the performance of the team.
So you fire Tim. Great! He was a slacker who didn't produce any story points. Now everyone is working individually. The other seniors don't have time to help juniors because they have their own stories to work on. Gotta keep those stats up...don't want to end up like Tim. The juniors start introducing bugs into the code accidentally. That's not good, their stats are going to go down. Except the one that picks up the bug fixes, his stats look great! He's sure to get a promotion doing nothing but fixing everyone else's mistakes. Then the other juniors start catching on, and start pickup up their own bug fixes that they introduced. Now the juniors are spending about half their time fixing bugs they created, while seniors start looking like slackers because they don't produce as many story points. Well something needs to be done about that, because you don't want to end up like Tim...
Any points system can be gamed. If all you look at are the numbers, you'll miss how the team really works.