When to replace brakes?

2014 prius 2. Purchased new in 2014. Has 130k miles on it. Brakes have never been replaced. I’ve gone in to 3 mechanics and all have said they’re fine. I get occasional squeaking but nothing consistent. I’ve never had a car go this long without needing some brake replacement and I’ve never known a mechanics to not try and up sell me something.

When have you guys been replacing your brakes?