I am the late Leah Hardy. I am always, invariably late. And far from thinking it’s some cute and quirky character trait, I hate it. It’s horrible, stressful and upsetting. It eats me up with guilt and makes my friends and family extremely cross with me. I’ve been late all my life. I’ve been late for school, late for university lectures, late for work, late for parties, late for weddings . . . late for every bloody thing. I’ve missed planes, parties and even vital job interviews.

Most people loathe latecomers. And not just because latecomers tread on their toes at the theatre or keep them waiting in pubs. It’s because they think latecomers are arrogant, power-tripping or simply disrespectful of other people’s time. British people are more intolerant of lateness than any other nation. A study by the delivery company Parceline Chronopost International indicated that the Japanese are the most forbearing, waiting up to 30 minutes with a smile. Only 8 per cent of Japanese think that you should never be late, compared with the British, of whom 34 per cent said any lateness is inexcusable. But we late people are not being arrogant — we are in hell. We are constantly stressed, rushed and miserable. Icy hands clutch at our innards as time ticks by and we realise that we are getting later and later.

Over the years, I’ve organised my life around my lateness. I often refuse invitations for events that have a specific start time as I fear letting people down. When I arrange to meet friends, I try to meet three friends, rather than just one, because then they have each other to talk to until I get there. If I arrive late at the theatre, I go and have a drink until the interval. I work freelance from home so I don’t have to start by a specific time. I moved house to be one minute from my son’s school gates. I even insisted on getting married in the same place I was staying as, otherwise, I’d have been late for that, too.

So why do I get myself in all this trouble? Why don’t I just pull myself together? After all, how hard can it be to just show up on time?

According to Diana DeLonzor, a time-management consultant and the author of Never Be Late Again: 7 Cures for the Punctually Challenged (Post Madison, £7.23), it can be difficult. “Telling a late person just to be on time is a little like telling a dieter to simply stop eating so much,” she says. “Though it may seem a simple matter of people being rude, it’s far more complex. It really is more than a matter of poor time-management. It tends to be a lifelong pattern. It’s something that goes across activities; most late people are late for everything.”

I e-mail DeLonzor at her office in San Francisco and she agrees to help me. By the time I call her a few days later (at the second attempt; the first time I forgot until it was too late) I’m ready to throw myself on her mercy. “Lifelong habits are hard to break,” she says, in her brisk, reassuring tones. “But it can be done.”

DeLonzor is living proof. She was terminally late for most of her life. It caused havoc in her job as a sales manager and chaos in her marriage. Like me, she offended friends, missed flights, and arrived late for business gatherings.

“It was a running joke but people also got angry,” she recalls. “Every encounter began with an apology or a story about why I was late. People always saw me as a bit of a flake.” I immediately experience a surge of sisterly feeling.

“Contrary to popular belief, it’s really not about being selfish or believing their time is less important than yours,” DeLonzor says. “These are people who are late for the gym, job interviews, even holidays. It’s about their inability to control their own time.”

DeLonzor, who studied lateness with the help of psychologists at San Francisco State University, has found that it is associated with certain personality traits. Among other things, the team found that punctuality-challenged people often share common characteristics, including anxiety, being messy and easily distracted, perfectionist habits, low levels of self-control or a penchant for thrill-seeking. I soon recognise myself as having other typically late traits such as procrastination and liking to fill every minute with activity. I am also slightly shy, and find social gatherings rather intimidating so I unconsciously put off the moment of arrival. I also, I discover, have a totally unrealistic idea of what I can accomplish in any given time.

Studies suggest that habitually late people actually perceive time differently from other people. At Cleveland State University, stop-watch-wielding researchers asked chronically late people how much time had passed, and were surprised by how much they underestimated time. DeLonzor replicated the research and found that early people, asked to read for 90 seconds, consistently read for less time, while late people carried on for minutes at a time. “People who are late tend to misjudge the time needed to accomplish even those things they’ve done hundreds of times, like getting dressed for work,” says DeLonzor. This is due to what she calls magical thinking — eternal optimism even in the presence of contradictory evidence. “It’s the unshakable ability to believe you can drive the ten miles to work in seven minutes flat.”

Research by the Medical College of Wisconsin, published in the journal Nature Neuro-science, suggests that certain areas of the brain are critical for time-perception. Poor time-perception, lateness, and impulsiveness are symptoms of certain conditions, including attention deficit hyperactivity disorder (ADHD), and these are associated with low levels of dopamine. It is possible, the researchers suggest, that late people may have mild brain abnormalities that are similar to those in ADHD.

Whatever the reasons for lateness, DeLonzor is convinced that, with the right amount of will and effort, it will be possible for me, and those like me, to change their ways. She instructs me to relearn how to tell the time: to work out how long things really take, and to base my schedules on the results. More importantly, I should never plan to be on time, filling every second until it is precisely the time to leave.

Ironically, most late people have a strong aversion to waiting. It makes them feel at a loss. In future, I must learn to love being early. If I’m due to start work at 9am and the drive to work takes 20 minutes, at 22 minutes to 9, the late person, instead of leaving the house, will continue reading the paper or doing the washing up until exactly 8.40am. This is a recipe for lateness, something that DeLonzor calls “deadlining”. Instead, I must plan to be 15 minutes early, and take a book or a paper so, if by a miracle I am early, I can treat it as luxury time, to treat myself to a chapter of a novel or a cup of coffee.

I should also, Boy Scout-style, be prepared. I should sort out my clothes the night before, put vital documents in my bag, keep my keys in the same place so I don’t spent ten minutes hunting for them. And lastly, says DeLonzor, I should banish my belief that it is pointless to do anything before I absolutely have to. Last-minute crisises constantly frustrate my attempts to be early, like the time I was late to a party because I ran out of petrol on the way.

“Put petrol in the car before the tank is empty,” exhorts DeLonzor. “Go to the cash-point while you still have money in your purse. Try to do three things early every day.”

I decide to put it all into action. I am due to visit a girlfriend’s new flat for dinner. I am supposed to arrive by 7pm, so aim to arrive at 6.45pm. The night before I pick out the dress I want to wear and ensure that it’s clean and ready to wear (instead of finding myself hopping up and down by the tumble drier at 6.30pm). During the day, I put petrol in the car. I make sure I have money. I ask my husband to come home 15 minutes early so I have time to disentangle myself from the kids, brush my hair and apply lipstick before leaving the house.

Things go remarkably smoothly — I’m early!

But I fall at the last hurdle. Just as I am about to swan out of the door, I hear the bleep of the answerphone. Before I know it, I’m in my office, checking my messages and e-mails. Realising that I am “deadlining” and run for the door. The journey (for which I have allowed an hour instead of my normal 20 minutes) takes exactly an hour. And, do you know what, I was on time. And if I hadn’t succumbed to the siren lure of the answerphone, I might even have been early. It is a revelation.

The next day I arrange to meet a friend in the park café with our children. I pick out their clothes the night before, instead of loafing in our pyjamas until ten minutes before we need to leave, I get us all washed and dressed an hour early. I have the paraphernalia of small kids — nappies, drinks, bananas — safely stowed under the pushchair. I leave 20 minutes early, which makes me feel deeply uneasy, even guilty that I’m not filling my time properly. We do arrive early, and I adore the feeling of smug satisfaction when I realise I have time for a coffee before my friend arrives. It is fabulously relaxing not to be sweating, flustered, and muttering apologies. My friend arrives on time, and is so startled to see me sitting there she assumes she is late and apologises, which makes us laugh.

I’m not saying my late days are over — far from it. But, thanks to DeLonzor, for the first time I am aware of some of the things that have always contributed to my lateness. My fear of not filling my time, my procrastination, and my reliance on deadlines have all been disastrous for my timekeeping. I am also aware that, for me, not being late will involve far more effort than for many others.

But for the sake of my sanity, and that of my friends and family, I just have to keep trying.

Never be late again

Stop doing everything at the last minute. Buy petrol before the tank is empty. Don’t start blow-drying your hair two minutes before you have to leave the house. Pay bills on the day you get them. Don’t plan to be on time, plan to be 15 minutes early. Take a book or some work with you to fill any waiting time. Make a daily plan, with a written schedule of your activities with estimates for start and end times. This helps you to see what you really have time for. The lateness guru Diana DeLonzor says that most people underestimate how long it takes to complete tasks by about 30 per cent. Create individual mantras, such as: “It won’t get any easier in five minutes,” instead of hitting the snooze alarm for the fifth time. Get more tips and advice from Diana DeLonzor at www.neverbelateagain.com.

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