Letting Puppies Knaw On Your Hand
Young dogs love to bite everything in sight. Though they may not bite very hard yet, the owner should not condone the behavior. If a puppy gets used to knawing on its owner’s hand, it won’t realize that biting is a no-no.

Zak George’s Dog Training Revolution/YouTube
Zak George’s Dog Training Revolution/YouTube
This can turn into a major issue when the dog gets older and stronger. Puppies grow extremely fast, so just a couple of months of nibbly playtime can turn into painful bites very quickly.