It isn't written in the lease? Most places I've lived have specified things like no holes larger than a quarter inch, or that you have to patch any holes you make. The last place we rented was a big complex. Any holes under 1/4 inch you could leave, any over 1/4 inch you had to neatly spackle, but they painted between tenants so you didn't have to repaint. Carpets were replaced every 7 years, so if it was due to be replaced and you damaged it, it weren't charged. Another apartment just stated that any damages would come out of the deposit. We put up bookshelves that needed an anchor at the top, but still got our whole security deposit back. I guess it was minor enough that it was considered normal use.
I'm also with melalvai. I don't worry about the security deposit. We treat rentals like our own - take good care of the property, pay our rent, maintain the lawn, but it's not a museum. I expect to be able to live places without freaking out about a scratch in the paint or a few nail holes. I don't think I've ever lost more then $50 out of the deposit though.