Just like a good shepherd...

Good design should anticipate, constrain or prevent users from actions that will lead them to errors.

Checks need to be made to inform users early on to prevent such occurences.

Do you have it?

Wherever you see a successful business, someone once made a courageous decision.
-- Peter F. Drucker

His first slide...

A quiet cellphone is a good cellphone.

We will confiscate all bad cellphones.