[raiflip]

> where some crappy code stuck and is in use 14 years later

I think this boils down to a roll of the dice. Its possible that some code is simple enough, or some engineer is smart enough, that tests are not really needed, but given the choice to not unit test would be made early, and its very hard to know the complexity of the solution at the beginning, you're really just rolling the dice with regards to whether it would work out. Sometimes you get a huge payout by delivering good code fast, but sometimes it can really blow up in your face with lots of prod errors.

Personally, I'd rather smooth out that large payout vs large explosion curve by just writing tests. If we could have pushed out the code faster, that is a loss, but if the code would have had many errors, thats a gain. So probability distribution with regards to payoffs is smoothed out.