Users are very much accustomed to accepting the security and privacy implications of conventional web logins. Persona promises to improve on that by introducing

Users are very much accustomed to accepting the security and privacy implications of conventional web logins. Persona promises to improve on that by introducing itself as a third party. However, users with a trace of security awareness will be skeptical of promises like that and will subconsciously do a simple equation in their heads: if everything else fails (the promised improvements), then more involved parties imply less privacy/security. Getting beyond that point requires at least a level of understanding that allows for a rough estimation on a scale between "totally bogus" and "this might actually work if done right".