Because she is afraid that it will pain and scratch her.
You should always, and I mean always, use a <u>coverslip</u> on your slide. Without it, the contents on it would slip off and there'd be a big mess.
For extra security:
<em>Always make sure your stage clips are working! :)</em>
<em></em>
I hope I helped! :)
Gravity acting on the edges of plates and the friction between the plate and the asthenosphere
