I worked at CAPCO for only a year and half and it was my shortest time ever spent with a company and the main reason was the extreme toxic environment. The competition amongst consultants makes the company extremely dysfunctional and demotivating.
Egos are at the same time inflated and fragile, making cooperation the rarest thing you'll see in the office. To exemplify, I was present when a colleague was in a call with a most senior consultant to get advices on a specific project. While the senior consultant was explaining something, my colleague mentioned he had had a problem (about the audio). Immediately, the senior consultant shouted (yes, shouted!) that if he was having a problem with anything that was being presented, he could ask someone else and stop wasting everyone's time. And hung out. That is how fragile and inflated egos can get over there.
Additionally, in this 1.5 year, I had 3 different managers and 2 CEOs, so needless to say how lost we all felt.