A great old post from @anildash
I really liked this:
▪ Is the idea grounded in a bedrock principle, based on humanity and compassion?
▪ Is the idea so simple to understand that people can articulate it to one another, even if they're not trained advocates?
▪ Is the purpose so obviously broadly beneficial that everyone can understand how it helps them or someone they care about?
▪ Is the goal so clear that everyone can tell if it has been achieved yet?
https://www.anildash.com/2022/01/31/you-have-to-start-with-the-principle/