Clock Spider Dangerous [PIC]

I actually like spiders but only the big ones. I want to be able to see where they are. I had a Rose Hair Tarantula a few years ago. One day she got out as I was cleaning her tank. I looked everywhere and couldn't find her. I was so upset. The next morning as I was taking a shower I looked up and there she was hanging on my shower curtain. I was so happy. I was also happy my Husband wasn't the one that found her. He would have screamed like a girl. :P
 
WOW!

I actually saw a spider that big once when I was on holiday. It was bigger then a dinner plate, but the pics I took just didn't do it justice!

Why didn't the spider move when the person removed the clock?