The sun might not, but everything else does. The struts supporting these things change with the temperature, the ground swells or settles, the tower may move a

The sun might not, but everything else does. The struts supporting these things change with the temperature, the ground swells or settles, the tower may move a bit, etc. Also, once the AI is written, you can save time on each install by not having to precisely locate each mirror. Get it close enough, and let the magic box fix up the small errors in real time.