Keeping your knives sharp is something you need to do from time to time regardless of what brand or make you get. When you use your butcher knives or any other knife for that matter you are slowly working the edge of making it duller. Because of this, it will need to be resharpened.
Keeping your knife sharp requires less force to cut and it helps you be more precise in your cuts and its safer to work with a sharper knife because you will not have to produce the force required of a dull knife that could cause the blade to push off and cut you.
When sharing a knife there are a few routes you can take. While this particular guide is on butcher knives we found an informative article on how to sharpen kitchen knives that you can read.