This is the best resources I've seen about Product-Market-Fit. Only geared towards B2B but still immensely valuable. Centers around repeatability as the holy grail, levels of PFM, dimensions and the 4 levers founders should focus on.

This is the best resources I've seen about Product-Market-Fit. Only geared towards B2B but still immensely valuable. Centers around repeatability as the holy grail, levels of PFM, dimensions and the 4 levers founders should focus on.
https://pmf.firstround.com/levels