How one missed Tuesday becomes a missed month

So far I've treated each skipped day as a separate event. But you'll have noticed that they cluster. One missed Tuesday tends to take Thursday and Saturday with it, and sometimes the following week as well. This chapter is about why, because I think the way zeros spread does more damage than any single zero.

Here's the sequence as I understand it. This is my interpretation, though part of it has research behind it.

You had a plan for the week, which was Tuesday, Thursday and Saturday. On Tuesday it fails. In your mind, the week is now damaged. You can no longer have a perfect week. The best on offer is two out of three, which is a flawed week. And a strange thing happens to motivation once a week is flawed. Thursday's session, which on Monday was part of a plan you were proud of, is now part of a salvage job. It's easier to let it go. "This week's a write-off. I'll start fresh on Monday." A fresh start is attractive because it's clean. It gives you back the chance of a perfect week, and all it costs is the rest of this one.

Researchers who study dieting have described something close to this. A person on a strict diet who breaks it with one biscuit often goes on to eat far more than someone who wasn't dieting at all. The reasoning seems to be that the day is ruined anyway, so it may as well be ruined thoroughly. I haven't found the same experiment done with exercise, so I'm drawing a parallel and not reporting a finding. But the structure is the same. There's a rule with no middle ground, then a small breach, and the breach gets treated as total.

The belief underneath is that consistency means an unbroken record, and a broken record has to be started again. There's good evidence that this is false for habits in general. Phillippa Lally and colleagues followed 96 volunteers who each chose a new daily behaviour. It might be eating a piece of fruit with lunch, or going for a run before dinner. They tracked how automatic it felt, every day for twelve weeks. The time it took to become habitual varied enormously, from 18 days to 254. The finding that matters for us is that missing one opportunity to do the behaviour did not materially affect the process. A missed day didn't set people back to the start. The habit kept forming as if nothing had happened, provided they carried on afterwards.

So the damage from a missed Tuesday is whatever you lost on Tuesday, and no more. The week isn't ruined and neither is the habit. No streak existed anywhere except in your head. The rest of the damage comes afterwards, from deciding that a flawed week isn't worth continuing.

This is where the ten-minute version does something beyond its own ten minutes. If on Tuesday at twenty to seven you'd walked briskly round the block for ten minutes, Tuesday wouldn't have been a zero. It would have been a short day. The week wouldn't be damaged, because nothing had been missed. Thursday would arrive as part of an intact week, and you'd be more likely to go. The ten minutes protects the sessions around it, and I suspect that's a good part of its value.

In practice, that means you don't restart on Monday. If you've had a zero, or a week of them, the next session is today and it's ten minutes. You haven't got a streak to rebuild and you haven't got a debt to pay off with a double session. The promise to make up for it, which chapter 1 listed as a feature of the habit, only raises the bar and makes the next zero more likely. Drop it, and do ten minutes today.