Why does habit chaining fail?

The most common reason habit chaining fails: Building chains that are too long before any single link is solid. A five-step chain where link two is unreliable means links three through five never fire. The other failure is invisible chains — sequences you run on autopilot that end somewhere you didn't choose. Chaining is powerful in both directions: it can carry you to your desk or to your phone.

The fix: Map one existing chain in your life. Pick a reliable morning or evening sequence and write out every link: 'After I [completion of A], I do [B].' Identify where the chain breaks most often — that's your weakest link. Now design one new two-link chain: pick an existing behavior you already do reliably and attach one new behavior to its completion. Run it for three days. If it holds, extend the chain by one more link.

The underlying principle is straightforward: The completion of one agent becomes the trigger for the next.