Perhaps we should try to convey useful advice in punchy ways to make them more memorable, and to encourage people to spread them. Aphorisms are probably very popular and widely shared because they convey information which readers likely already know, but which hitherto had never been shared in such a witty, laconic way. Reading an aphorism prompts you to think, "Wow, this is true, and it is so eloquently expressed -- funny how I didn't think of saying it like this." People tend to remember aphorisms better for that reason, and they also tend to share aphorisms more often with their friends, because they want to come across as witty themselves.