Genuine question, as I want to learn from this (as I run similar service). If you were to launch one such critical service, what would you do differently to ass

Genuine question, as I want to learn from this (as I run similar service). If you were to launch one such critical service, what would you do differently to assure your customers that you really care & won't screw them behind their back? Definitive answer is: first of all don't screw your customers. But how do you make sure you convey, you won't?