A story of an employee who is going to work in one of the big4 companies

"Can you explain the "forced ranking" system (e.g. GE style) that the Big 4 use to weed out employees.
Good question. There are really three factors that come into play here -
a) CPA - This is huge. If you don't have it after 4 years at your firm, you're in the red zone. Try and get it out of the way as soon as you become eligible to take it. If you are not a good test taker, then it is even more imperative to begin the arduous process asap. If you are an audit superstar, but still don't have your CPA by this time, you're in danger. Why? Because it is a numbers game, and since firms have to cut a certain number, they just look at stats and don't look at each individual's particular scenario.
b) Performance Reviews - Don't aim for an average rating. In this economy, it's not good enough. Yes, if people know you're good, you might end up getting put on horrendous clients. But that's just a risk you have to take. Take more responsibility for what you do. Help your senior associate/manager in any which way you can. Trust me, he or she will really appreciate your willingness to help (assistance, not brown-nosing). If you go below average w/ different reviewers, update your resume.
c) Hours - If you're sitting around in the office "on the bench" and not working much for days/weeks, don't wait for somebody to assign you to certain clients. Go seek out your managers/senior associates and ask to be put on clients. This is a very easy metric for HR to measure, and if they notice that you're not being used effectively, you're expendable.Then again, if people start leaving the firms, then they'd go back to the pre-recession days of their economic model, i.e. constantly be short of auditors instead of having an excess to carry around on their books.