I have another one for you: Consider what else could be the problem.
Maybe they aren't fools at all. Maybe you aren't one, either. Maybe stupidity just isn't involved in the struggle for someone to accept or adopt an idea or technique.
What else could it be?
There's no way to enumerate all the possible reasons why someone might be having difficulty. Here are a few common ones:
- Someone is afraid of something.
- Someone already has a way that kind of works and they don't want to lose that.
- Someone has change-fatigue.
- The change in question is too big for someone to digest.
Each of these problems is eminently solvable. No emotional response is required.
If someone is afraid, explore the fear and figure out how it can be assuaged. If someone doesn't want to give up something they think is helping them, add rather than replace. Let people rest between changes and enjoy the benefits as a salve for change-fatigue. Decompose big changes into sequences of much smaller changes.