Probably because you have to make absolutely sure that the things you sign are a...

claudius on Nov 3, 2013 | parent | context | favorite | on: Ask HN: Why is PGP not used widely?

Probably because you have to make absolutely sure that the things you sign are actually the things sent by the webmail provider, and if they decide to add random stuff, the signature will fail. Encryption is, in some sense, easier.