Surprising. I didn't know this construct and I would naturally assume that the else part would execute if the loop never spun (because the list/etc was empty)

Yes, the else keyword is not intuitive. The best way to remember for/else is for/nobreak

Right! nobreak would make it much clearer.

It would involve adding a new keyword to the language though. I imagine there was some desire to avoid that.

This was my guess too.

Relatedly there's also a try/else, where the else block only runs if there wasn't an exception.

All these else variants come in handy from time to time.

The most common use case of for/else for me is:

for/len==0