Client picked up her glasses three days a go and she came back because one of the lenses were crazed, it was replaced and than she came back again because the other one got crazed when it wasn't before, strange.

What are the reasons they craze? Bad batch? Should I ask her what she does for a living? I know sometimes if the lens is inserted to tight it can happen but she's definitely doing something to craze them.

I was thinking of giving her a easy clean coating.

What do you guys think it can be?