I worked at an Investment Bank that did stack ranking and I worked with very smart people. So smart they figured out that helping out new guys on the team did a

I worked at an Investment Bank that did stack ranking and I worked with very smart people. So smart they figured out that helping out new guys on the team did absolutely nothing for them- any time spent not working on their specific OKRs was just detrimental to them. There was no incentive to help new guys on the team, and they were happy to just let them sink or swim. I couldn't stand to see that, so I would help mentor the new guys, and it often did cost me a lot of time and affected my deliverables. The joke was on us though- everyone was fighting for a bonus pool that largely didn't exist (this was in the aftermath of the financial crisis). Your only way "up" was to get out.