One example near me is NXP, a semicon business from Eindhoven (NL) where I live. Philips spun them out after loading them with debt,a PE firm bought them. Radical cost cutting, the usual, but they also accomplished a culture change (to some extent). As a former Philips department, the culture was very slow and bureaucratic, more akin to government than a for-profit business. The new owners made it very clear that from then on, money needed to be earned and anything that didn't contribute to that wasn't worth doing. The company became a fair bit more lean and agile as a result, pushing products and updates faster etc.
Customers typically aren't affected but employees are.
This is fundamentally untrue. Large CAP ($1B+ valuations) is notorious for this, but there's about 5k PE deals per year and those deals are the exception, not the norm, in terms of shear volume. They're great for headlines though! (hello Toys 'R Us)
Most of them are about adding value through various means, one of those might be cutting unnecessary costs.
So let's take it as read that you meant PE, in that case, it depends is the usual answer. There are quite a few examples of PE funds buying companies and letting them run as autonomous as possible with positive results and there are examples of PE funds buying a company outright or a controlling interest who then become 'backseat drivers' but without the relevant experience. In those cases - especially if the PE party consists mostly of accountants and financial people - it usually does not take long before the effects become visible. But there are a great many players and the majority of them is both well intentioned and ends up with positive results. The ones you hear and read about in the newspapers are not really representative for the PE market as a whole, that's just the news' habit of focusing on the trainwreck.
PE fund returns nX to their LPs versus PE fund buys controlling stake in struggling company and runs it into the ground after loading it up with debt. Which headline do you think will attract more eyeballs?
First, VC doesn't acquire businesses, PE does.
Second, I've seen NUMEROUS examples of entities acquired by financial sponsors (PE) that work out well.
If you look at Vista Equity, Thoma Bravo, Silverlake, TA Associates, Accel-KKR, etc. you'll find an incredible amount of wealth being generated.
PS - Depends on what you mean by "turned out great"...
Note: am employee.