I also never let my brushes get paint caked in them. While painting, I make sure not to get paint more than 1/3 the way up the bristles. Above that and you start having problems getting them clean. I rinse thoroughly with warm water, while gently squeezing the brush and straightening the bristles until the water runs clean. I lightly tap the water out, straighten and smooth the brush and then hang it, brush down to air dry. Once it's dry, I put it back in the cover it came in. An old painter taught me to do it that way and my brushes last through several years of moderate use.