But we're talking about "seems competent and has a reasonable chance of being very productive". That's why you're interviewing in the first place. If you don't ask them to demonstrate their competence in any way how do you know they're competent? If they can't "produce" anything during an interview (even something trivial) how do you know they'll be productive? Assuming a complete stranger with no references you can trust.
A month might be too short of a time for certain roles. I think people would be hesitant to take a risk with you if they know this is your policy. I'd would say that at any point where someone is clearly not a fit they should be let go. You might know after a month (if they're terrible), you might know after 6 months, they might progress initially but stall. I think e.g. with new grads it's going to take a little longer in general since they have a pretty long growth trajectory.
A month might be too short of a time for certain roles. I think people would be hesitant to take a risk with you if they know this is your policy. I'd would say that at any point where someone is clearly not a fit they should be let go. You might know after a month (if they're terrible), you might know after 6 months, they might progress initially but stall. I think e.g. with new grads it's going to take a little longer in general since they have a pretty long growth trajectory.