It's actually an hour per month plus one. So for an 8 week old puppy, he should be able to stay crated for up to three hours.
Crate training not only makes sure the puppy isn't pooping or peeing in undesirable places, it also keeps puppy out of trouble. You'd be amazed at how "good" electrical cords can taste, or how fast a puppy can demolish a pile of shoes. The only way to ensure that a puppy is not doing things it should not do, particularly when you are sleeping or otherwise unable to watch it, is to have a way to confine the puppy.
I have five dogs in the house. Three sleep crated, the other two loose. Of the three that sleep crated, all three of them will follow me into the kitchen at bedtime, see me grab the cookies, and then make a bee-line to their crates. The crated dogs are 1 yr, 18 months, and 20 months. All are high drive dogs and like to get into trouble at night... picture three herding dogs playing with three cats at 2am. Sigh. The older two Belgians are much too dignified to resort to chasing a cat in the house, or chewing shoe, or anything else for that matter, but, if I tell them to "go to bed", they will enter the nearest crate willingly.
Charlotte
Spiritus Reg'd Belgians