Because the jacket is GoreTex, it is designed to be washed. Goretex works best when it is clean. I have a jacket with a similar shell fabric, the DWR Coating is restored when i put my jacket in the dryer. Water just beads right off. But, this isn't what makes the jacket waterproof. The Goretex is a membrane that is usually bonded to the backside of the outer fabric, this is what actually keeps the water out.
Most other jackets are not designed to be washed regularly in the washing machine. I wear my jacket for any type of weather. It works great. The AK stuff is very high quality, and does what it is meant to do very well.
let's not talk about it