4? phases of hair growth?

I seem to have read somewhere that there are 4 (I think) phases of hair growth. Am I right to assume, then, that we see only one quarter of our hair at any given time? So if we are lasered three quarters of our hair is still with us ready to erupt at some future date? That would explain people getting upset about the dismal results they think they got when hair returns later. It’s not the same hair.

Correct me if I’m wrong. It’s just a bit of logic that came to me as I was drifting off to sleep. I’d like to see something about the phases of growth that have been mentioned but not clarified.

Cheers

You can read all about hair growth and percentages of actively growing hair by body areas here.