Think about the last meeting you attended or the last appointment you had. Did you arrive right on time, or even early? Or were you--just a little bit--late?

Go ahead, admit it. I'll confess that I'm no paragon of punctuality myself. And I have lots of company. Recent research by Blue Jeans Network shows an astonishing 81 percent of meetings fail to start on time. But just because tardiness is rapidly becoming the norm doesn't make it OK. For all of us who've let sloppiness about time turn into a daily or weekly habit, it's time to stop.

Here's why:

1. It's impolite.

I come from New York City, and although it's a wonderful town in many ways, it's arguably the rudeness capital of the world. So I wasn't surprised to learn that people on the East Coast are the worst offenders when it comes to showing up late for meetings.

Being late always communicates the same deeply impolite nonverbal statement: "My time is more valuable than your time." Even if that's true because you're the boss, it will demoralize employees and make business partners reconsider whether they want to work with you. It's a terrible message to send under any circumstances.

2. You won't be at your best.

There are very few people in this world with enough self-confidence, or self-importance, that they truly don't care what others think of them. Unless you're one of those people--and I'm certainly not--being late is bound to rattle you at least a little as you head into your meeting or appointment. Are people resentful? Did you miss anything important? Should you have skipped stopping for that last cup of coffee or errand?

Having these worries bouncing around in your head will make it harder for you to focus on the matter at hand, whatever it is. You'll be distracted. And you probably really will miss something important.

3. You'll waste other people's time.

If you're the boss, this may not seem like a big deal, but think about it for a moment. The people you supervise depend on you for their jobs, but you depend on them for the successful performance of your department or company. If you're an entrepreneur, you may be paying them from your own limited resources. Why would you want to undercut their efficiency, not to mention their morale, by leaving them to sit around and wait for you to show up?

4. You'll worsen your company's culture.

You want a culture in which people are accountable to customers, to their peers, to themselves, and to you. But chronic lateness sets a tone about accountability, and it's not the tone you want. Being on time may seem trivial in the scheme of things, but it's a good place for accountability to start.

5. Tardiness becomes a vicious cycle.

If your employees know every meeting will dependably start at least five minutes late, do you think they'll bother showing up on time? Would you, if you were in their shoes? When people show up late for a meeting and find it hasn't started yet, that provides confirmation that the time they arrived was actually the right time to be there, and they'll be at least that late next time around. Meantime, those suckers who arrived when they were supposed to and had to sit around playing Candy Crush won't make that mistake again--they'll show up at least a few minutes late next time as well. Eventually, you'll have created a workplace where no meeting ever starts when it's supposed to, and people show up to meetings later and later.

The only way to avoid this is to start meetings on time no matter what. I know--because I used to routinely show up a few minutes late to board meetings at the American Society of Journalists and Authors. That was just fine, up until about a year ago when we started working with an association management firm that told us we should start and end every meeting on time whether key people were all there or not. We took that advice. And we're all a lot more punctual now.

6. Modern technology means there's no need to be late.

You can set your calendar or your watch--or both--to remind you when it's time to leave for a meeting. Map software, including your car's GPS, can tell you exactly how long it will take to get where you're going. These items, not to mention Waze, can also tell you how bad traffic is along your intended route and suggest alternatives. So while there may always be unforeseen occurrences, such as an accident just ahead of you, most days you have all the information you need to arrive anywhere on time.

7. Mobile technology means you won't waste your time if you're early.

Most of us can do all or most of our work using some combination of smartphone, laptop, and tablet, pretty much anywhere there's a cell-phone signal or available Wi-Fi. So there's no longer any need to stay in your office finishing up one last thing before you head to a meeting. Throw the laptop or tablet in your briefcase and the smartphone in your pocket, and leave early. You can sit and work wherever you are while waiting for the meeting to start.

8. A commitment to being on time forces you to schedule appropriately.

Overscheduling is behind much of my chronic tardiness, and I'm sure I'm not the only one with the bad habit of thinking I can always squeeze one more thing into any given day. But if you pay attention, it doesn't take long to see how overscheduling yourself tends to force you into tardiness. If you make punctuality a real priority, it will force you to create a realistic schedule and say no to some things that just don't fit. That's a plus for you and for everyone around you.

9. You'll have a happier and more efficient workplace.

Creating a saner schedule is just one benefit you'll get from a commitment to being on time. The people who work with you will feel more respected, and they'll be able to use their time more efficiently as well when they're no longer wasting it waiting for meetings to start. With meetings starting on time, your chronically tardy colleagues and employees will be motivated to start showing up on time rather than arrive at meetings already in progress. They, and you, will develop a reputation for punctuality and reliability. You'll all be happier.

That sounds like a pretty good deal all around.