Before you start

This is a short book and you can read it in two or three sittings. It's about one habit. You're late. Not always, and rarely by much. Five minutes to the meeting, ten to the dentist, twenty to dinner at a friend's house. You arrive a little out of breath, say sorry, mean it, and do the same thing on Thursday. You've been told you're bad with time, and you've come to believe it. You may also, privately, think that punctual people are making rather a fuss.

I'm going to argue three things. The first is that running late makes sense from the inside. You don't like waiting, you don't like wasting time, and you like getting one more thing done. Those are reasonable tastes, and the habit is what they've turned into. The second is that the habit rests on a mistake about time that almost everyone makes and that you make more often than most. Your idea of how long things take is a best case, not an average, and experience doesn't correct it, because memory shortens the past and every late arrival gets filed as an exception. The third is practical. You stop aiming at the place and start aiming at your own front door, and you set the time you leave from your own record and not from your hope. Chapters 16 to 19 cover how.

This book doesn't say that being on time is a moral quality, or that punctual people are better people. It says that lateness costs you more than you've counted, that most of the cost falls on people you like, and that the cure is a change of arithmetic, not of character.

Three cautions.

If you've had trouble organising your time all your life, along with losing things, being easily distracted and finding it hard to finish tasks, and these things are affecting your work or relationships, they may be signs of ADHD. The NHS advises seeing a GP in that case. This book may still help with the particular habit of leaving late, but it isn't a treatment for a condition, and it doesn't pretend to be.

If you've recently become late to everything, having been reliable before, and you've also lost interest in things, sleep badly, or feel low most of the day, treat that as a change in your health and not in your timekeeping. Talk to a GP.

And if you're late because you're carrying more than one person can carry, with small children, an elderly parent, two jobs, or all three, you don't have this habit. You have a load problem. Chapter 20 says a little about it, but the answer there is help, and not a better estimate of how long the walk takes.

The notes at the back give my sources and their limits. Where I'm giving my own reasoning and not a finding, I'll say so.