Why would people pay exorbitant rents rather than just buy a house?

[Ava G.]

I am starting with REI so pardon my stupid question.

Investing in Real Estate, for the most part, has got to do with the confidence that there is an abundant number of people who are willing to rent a place (instead of buying a house themselves).

But does it follow that if someone can afford an expensive rent, they should also be able to afford buying a house?

I do know some obvious reasons (e.g. they are not going to stay there for long)... but what would be the other reasons, especially for long-term tenants? I just like to know a bit of psychology behind it.

Or for BP members who have a lot of tenants, would you be able to share their reasons for renting?