How often do PE firms replace senior management?

Not in PE, so take what I say with a grain of salt, but I have been to a fair share of interviews and alumni discussions and have asked this question before. The answer is it really depends on the specific PE firm's approach.

Quality senior management is typically a key criteria, along with steady cash flows, low capex req's, significant comp adv vs. peers / market leader or recognized growing niche player, growing industry, etc. With some firms, a quality sr management team (e.g. one where the team has say 10+ yrs working with each other, 10-20 yrs in the industry, have significant capital invested in the business, have deep ties with the employees and middle/sr professionals and involvement helping with succession planning) is the top criteria. And then, there are PE firms that place much more emphasis on company fundamentals and if they believe it needs a new direction and the management in place is incapable of executing new/future plans, they will find a new team.

A lot of the firms I met with didn't like to change management unless it was a big issue. And one PE firm I met that likes to consider targets with 'hair' on them are not afraid of cutting management and have done so numerous times. So firms that focus more on turnaround stories would probably put in new mngt teams more often.

Generally though, I think PE firms don't like to/are hesitant to making radical changes to senior management. Unless there is a serious problem (the company's a turnaround story and sr. mngt hasn't improved or worse caused the downfall), there's a trickle down effect on the employees and culture. If it was a terrible team, then it makes sense for everyone, but if there's just a few minor points to improve - it may make more sense to keep the management team and maybe bring in a few new people to integrate to balance out the team, or for succession if it's a situation where the experienced owner doesn't have kids/relatives capable of taking the reins.