In my experience, in climates like Southern California, lemons and figs put off the most fruit. Lemon trees even more so.
We had lemon trees, and my Aunt does also, that no matter how much you prune, neglect, don't water, let get overgrown, etc. it will still put out amazing amounts of lemons. The fig tree was was one in particular, that thing never stopped. It was really kind of amazing.