Don't Cut Corners when it comes to your quilting cutting supplies Rotary Cutters get dirty! Remember to clean the cutter when changing blades. Lint builds up under the blade.
Change blades often -
If you accidentally roll the blade over a pin, corner of a ruler or other hard object, the blade will be damaged and leave portions of the fabric uncut. Remember this when you are purchasing blades - no matter the price they are redundant when damaged.
Blunt blades will damage your cutting mat, whereas a sharp blade has minimum penetration allowing a self-healing mat to work effectively and allows less fabric lint to enter the cut.
Have you noticed when you open the packaging of a new blade that is has a little smear of oil on the blade? Do not wipe it off as it allows a smoother cut. In fact, you should oil your rotary cutter blade as you should oil your scissor blades.