This.

I became a licensed ship's electrician a decade and change after doing my MSc in RF design - turned out that in the line of work I stumbled into, doing control systems for heavy offshore equipment, it was a massive benefit to be able to work hands-on on the systems during commissioning, rather than pointing at the stuff which needed doing and trying to agree with some poor guy I more often than not did not share a language with as to what I meant.

The supervisor at the local trades office had a laugh at that when I called and asked if I could get to take the test(s) based on relevant work experience rather than by having served a conventional apprenticeship.

Most often, the ones asking to take that path had started working as cable pullers and helping hands at fifteen; having an MSc ask was... ...uncommon.

It was quite the experience learning HOW to do all the stuff I knew needed doing.

Anyway - I can now do all sorts of rather competent work on a ship.

I'd be utterly useless (as well as in violation of the law) if I ever attempted to do anything in a house.

The latter has been very helpful - seeing as I've been asked often whether I can help out friends and relatives with electrical installations at home, seeing as I'm an electrician and all.

Sorry. Against the law. Phew.