Getting your reason clear

The motivation you feel on day one — clear, certain, a bit fired up — will not be there on day four. That's not a character flaw; it's just how motivation works. What carries you through the low points is a reason you decided on in advance, in your own words, that you can look at when the feeling is gone.

Make it specific

"I should probably cut back" doesn't hold up at 9pm on a bad day. These do:

• "I want to remember what I did yesterday."
• "I'm spending £200 a month I'd rather put somewhere else."
• "I don't want my kid to grow up thinking this is just what evenings are."
• "I want one year of knowing whether the anxiety is the weed or me."
• "I'm tired of planning my day around when I can use."

Pick the one or two that are actually true for you. Not the ones that sound the most responsible — the ones that would still mean something to you if no one else ever read them.

Write it down where you'll see it

The point of writing it isn't ceremony. It's that a craving is very good at making your reasons feel abstract and far away, and a sentence you can actually read pulls them back into focus. Keep it somewhere you'll pass by it — a note on your phone, the app's reason field, a card by the bed.

Revisit it, don't just set it

Your reason can change as you go, and it usually does — the thing that got you to quit isn't always the thing that keeps you quit. After a few weeks, the "I want to remember yesterday" reason might turn into "I like who I am without it." Update it when that happens. A current reason works better than an old one.