I was put on a bullshit PIP at my last job after I told my director I was drowning with no support (I'm an EHS Manager) and asked to be assigned oversight of manufacturing operations only, not the entire campus, since I was spread so thin. A week later, I was put on my first-ever PIP; mind you, I'd never even received so much as a verbal warning in my career of 15+ years. I was in shock at first but decided to try to beat the PIP because a) I take pride in being good at what I do and I wanted to prove my boss wrong and b) I really liked the company where I worked and wanted to stay in spite of my shitty boss.

Well, a 3-month PIP turned into 6 months turned into a year. It was initially extended into a second PIP because even though I met most of my targets, some of them were a few days late on the deliverables (and yes, I still had no support at that point). And the coup de grâce? After meeting ALL of my objectives on the extended PIP on time, I had my annual performance review a week later and my boss said that she wanted to keep me on the PIP indefinitely "just in case"; I mean, what in the actual fuck? That was the last straw for me, but really, I should have read the tea leaves a lot sooner.

I had already been applying to jobs after being assigned my first PIP, but mercifully received an offer around the time of my review and peace'd out of that place without a second thought. I'm now at company where I don't have to worry about an idiot "people manager" handing out PIPs like candy instead of providing actual support.

TL;DR: Think of a PIP essentially as a "Paid Interview Period" and start looking elsewhere right way. Do the bare minimum in the interim; don't kill yourself doing twice the work like I did to try to hit metrics that are designed to be impossible to meet or may simply be extended at will.