Boiling (bowling) point(s) - which is correct?

I hear two seperate definitions of boiling point, with different benchmarks as well.

One is a hard number: step one- $100k and then- critical mass of $500k.

The other one is: Step one -your investments are making more than you are saving, and step two- your investments make more than your income.

It doesn't matter much which is correct, but what do y'all think? Or do you have another definition? Or did I miss another point, like when invesmtents make more than expenses?