The No. 1 Trait I Look For When Deciding to Do Business With Someone As a widely recognized marketing consultant and public speaker, I always look for one thing before I do business with someone — you should too.

I'm sure there are exceptions somewhere, but so far, in 50-plus years of noting this, everybody I've met and gotten to know who devoutly adheres to this discipline has become exceptionally successful, and everybody I've met and gotten to know who ignores this discipline fails.

Is it possible that this discipline alone is so powerful that it determines success or failure?

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The discipline that I am talking about is punctuality. Being punctual. Being where you are supposed to be when you are supposed to be there, as promised, without exception, without excuse, every time, all the time. I cannot tell you how important I believe this is. But I'll tell you some of the reasons why I believe it is indescribably important.

First of all, being punctual gives you the right — the positioning — to expect and demand that others treat your time with utmost respect. You cannot reasonably hope to have others treat your time with respect if you show little or no respect for theirs. So, if you are not punctual, you have no leverage and no moral authority. But the punctual person gains that advantage over staff, associates, vendors, clients and everybody.

Secondly, punctuality shows you who you can trust. It is my conviction that a person who cannot keep appointments on time, cannot keep scheduled commitments, or cannot stick to a schedule cannot be trusted in other ways either. I am amused by people scheduled to meet me somewhere who are perplexed that I don't carry a mobile phone. "How will we reach you if we're running late?" they ask. "You won't," I answer. "I'll be where I'm supposed to be, so I won't need to call you. If you aren't, I don't want to hear from you."

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One of the reasons my speaking career flourished — I spent nine years on the a seminar tour and lived on repeat engagements — is because I could be counted on to be there, on time, ready and low-maintenance. Others cut their flights too tight and were often late. I watched others drive the meeting planners and promoters crazy with this unprofessional behavior.

In my mind, it was a matter of integrity. I had made an agreement. Fundamental dishonesty expresses itself in many ways, but this is definitely one of them. You will save yourself a lot of time and money if you take notice of the habitually and chronically late and rid yourself of them. There is a link between respect for others' time and respect for others' opinions, property, rights, other kinds of agreements and contracts. A person reveals much about themselves by their punctuality or lack thereof. So, as a general rule of thumb, I use this to determine whether or not I want to do business with someone.

A simple way to favorably impress others

Here's a success secret for you: I'm not the only person to have figured out this punctuality-integrity link. I'm just not that smart. I've stumbled on something that a whole lot of other smart, successful and influential people already know and secretly use to make their determinations about who they will buy from or not buy from, do business with or not do business with, help or not help, trust or distrust. If you are not punctual, others you wish to influence positively will negatively judge you.

"By all means, judge. But know that you, too, will be judged."

In doing research for two of my other books I uncovered that many affluent customers, clients, and investors used punctuality as a litmus test for integrity. If you think that successful people — people you want to deal with — do not have their own little "systems" for judging people, you're very naïve. Not only do they have such a system, but most successful people make a point of having "instant reject criteria" to save time in determining who they want to deal with and who they don't.