What does it mean that reliable triggers are specific and observable?

A trigger must be something you can detect consistently.

Example: You set a trigger: 'When I feel stressed, I'll do a breathing exercise.' Three weeks later, you've done it twice — not because you lack willpower, but because 'feeling stressed' is not something you detect reliably. You're often stressed without recognizing it until hours later. Now compare: 'When I close my laptop lid at the end of the workday, I'll do three slow breaths.' The laptop lid closes the same way every time. You never miss it. The trigger fires every single day.

Try this: Pick one behavior you've been trying to start. Write down the trigger you've been using. Then score it on two dimensions: specificity (could someone else observe the exact moment it occurs?) and observability (do you reliably notice it when it happens?). If either score is low, redesign the trigger to be a concrete, visible event — a specific time, location, or action you already perform daily.