CPANTS is a testing service for CPAN distributions. One of its goals is to provide some sort of quality measure called Kwalitee. Though it looks and sounds like quality, higher Kwalitee score doesn't always mean a distribution is more useful for you. All it can assure is it's less likely for you to encounter problems on installation, the format of manuals, licensing, or maybe portability, as most of the CPANTS metrics are based on the past toolchain/QA issues you may or may not remember.

If you are a CPAN author, search and visit your Kwalitee report page, and fix at least core fails (if any) for better CPAN experiences.