When we see large account balances, in the thousands of dollars, that's usually a situation when fraud is involved.
We use a gentle tone of voice. We let patrons know that the library isn't angry with them, and wants them to return the books.
It's real important to our customer libraries that patron goodwill be protected. So we use a gentle approach. We help patrons understand the importance of libraries to their communities and most patrons respond.
If there is an open obligation to a library, a person can be denied credit, but once it's cleared, it has a negligible effect.