Because otherwise they would be unable to track movement and move the cursor in the computer screen.
It pokes holes in condoms.
Just in case he gets a hole in one!
Covers tracks
All seven or eight of them.
Stop with the cheesey jokes!
Because they squeak!
I'm having a movement
His vision was based on movements.
He wanted to check his e-mail.
Because your foot would go right through the computer screen!