1. Data should be self-describing, without external tables needed to interpret the file.
2. Conventions should only be developed for known issues, and features should only be added as needed.
3. Conventions should be easy to use, both for data writers and users of data.
4. The metadata and its meaning, as encoded in the conventions, should be readable by humans as well as easily used by programs.
5. Redundancy should be minimized to reduce the chance of inconsistency.

2009 Unidata NetCDF Workshop for Developers and Data Providers > CF Conventions