> If the code has no author ... there's nowhere to go if you realise "oops, I didn't understand that as well as I had thought!"

That's also true if I author the code myself; I can't go to anyone for help with it, so if it doesn't work then I have to figure out why.

> Believing you know how it works and why it works is not the same as that actually being the case.

My series of accidental successes producing working code is honestly starting to seem like real skill and experience at this point. Not sure what else you'd call it.