When governments and related agencies implement this it is called no wrong door.

I like it. It doesn't have to take any effort. When you hit reply on an email sent to the wrong person, add the correct email to the field with recipients. That's it!

In something like Slack, you write the answer in the correct location for the question. That's it.

These are tiny changes that don't cost anything but can decrease friction a lot, because the nobody has to repeat themselves any time someone has gone through the wrong door.