Everyone says enforced naps are good – but what are they?

Hello – I am stuoid and don’t understand the lingo. I am hearing a lot about puppies needing enforced naps in a crate but what does that mean? If we are on a schedule and it’s time for the nap and we put the puppy in crate but they don’t sleep and cry for 2 hours is that an enforced nap or what is it? I hate myself.