Indeed. Some of the worst software interfaces I've ever dealt with were fully "dogfooded" and that was the cause; the people writing the software did use it every day but (a) in a very idiosyncratic way and (b) in a specific, very constrained environment.

The devs did use the software, but used it in such a different way from everyone else that when the devs optimized for their own case, it made the software actively worse for everyone else.