A system with a user in the loop can have significantly lower reliability of input and still be viable as a system.

As long as it's above some "good enough" threshold where the user can detect the error and fix it easily (perhaps tweaking the input to try again), then the outcome is viable for that use case.

The user can correct small mistakes early before a lot of execution on them makes it harder to fix later.

It's a more forgiving bar to hit.