Comment by peteretep

Exactly. An excellent recruiter will build up a pool of candidates and clients who want to work with them, and will start their own agency where the compensation is usually a multiple of what they'd get in-house.

In-house recruiters tend to be one of:

* HR professionals who do some recruitment as part of their job

* A surprising number of people who end up taking on some recruitment responsibilities as part of their secretarial or admin work, and then end up doing it full-time

* Agency recruiters who didn't enjoy or could cut it being agency recruiters

I know a small number of excellent internal recruiters, but they're really the exception not the rule.