Whereisthelostkey's journey

I recently discovered that my manager intends to place me on a Performance Improvement Plan (PIP). This is particularly unsettling for me as I've been in my current role for over 10 years and have never faced anything like this before. I'm trying to assess whether I truly deserve this based on my performance compared to my colleagues. If it's a toxic environment, I'm also considering whether it might be better for me to leave voluntarily rather than go through the PIP process.