Whenever I have taken the small amount of cryptography knowledge I already have and tried to use it in a project, I've often been shutdown with "the system alre

Whenever I have taken the small amount of cryptography knowledge I already have and tried to use it in a project, I've often been shutdown with "the system already does that" when it doesn't, or "this will be too complicated for the user, instead lets just roll our own [ad-hoc cryptography method]". For those reading: How do you convince people that it's worth using best practices? Is there a good heuristic to measure the value of something, when deciding how much time and money to spend on securing it? What are good library/SaaS solutions to help build secure applications with less chance of shooting yourself in the foot, better UX and lower cost? (Keybase, etc.)