Friction slows action. Usually we want to remove it. But sometimes friction is useful. It creates a pause that allows better choices.
Add friction to undesirable behaviors. Delete the app instead of just closing it. Keep the credit card in a drawer instead of your wallet. Make the bad choice harder and you will make it less often.
The pause that friction creates gives the rational mind time to catch up with impulse. That extra moment is often enough to choose differently. Not willpower, just delay.
What useful friction could you add to a behavior you want to reduce?