One of the most dangerous things in a kitchen is a dull knife. (And mandolins without guards!)

Dull knives require multiple times of stress, and sawing motion to abrade through the thing. And with more power means accidents are easier and more damaging.

A proper chefs knife (I prefer santokus) should be professionally sharpened, honed before each use, and will be razor sharp. I only need to lay the knife on a steak and pull, and it cuts right through. The cheap $20 knives are usually serrated (nigh unsharpenable) and double as hacksaws.