I'm not forced to program at all. I do it because its most always held my interest. I've passed my 10,000 hour mark years ago. So for those that program well and do so by choice, why can't we spend our time focusing on defining good clean interfaces on the "real" code instead of the tests?

Well, don't get me wrong, I've seen my share of codebases with "Iface" and "Impl" classes (ew), and stupid, counterproductive unit tests that were done to check off boxes on a PM's checklist rather than improve stability. My favorite was a test to ensure that some static method somewhere returned the same hard coded string every time. The method was one line long, 'return "foo"; '.

But. If you've defined nice clean interfaces, and a particular module has complex behavior that will have to evolve over time, then adding tests to certify that that behavior is correct shouldn't be too much of a chore -- and they save your bacon when you need to change it and track any regressions afterwards.