Here’s an observation—the busiest, most successful people in business are the ones who follow-up when they say they will follow-up.

Those who tell you they will get back to you and don’t are not at the top of the food chain, no matter what they think. They are insecure, weak, or hiding something. These are people who are there when they need you, invisible when you have nothing to offer them. They are not just disingenuous, they are deceived.

I’m not talking about the person who won’t return your cold call. That happens, although the best executives I have ever met are the ones who will give anyone at least a single chance with a cold call. I’m talking about the person who asks to see your business plan and then never gives you feedback. I’m talking about the company that posts a job online, and then ignores the applicants who pour out their hearts in their submissions. I’m talking about the person in your network who knows you well, whom you ask to read your proposal, and then when you follow-up ignores you. That’s not just bad manners—it’s bad business.

I can’t tell you how many of the people I mentor relate utter frustration at being ignored by former colleagues they once counted among their contacts. Many of these same people are still out of work from the recession, apply for an open position, hear nothing back, and when they call or email, still hear nothing back.

The sound of silence is not a sign of importance or strength. It’s not a sign of how busy you are. It’s a sign that you did not have a good boss on your way up who taught you how to play the long game. All of the great bosses I’ve had—and some were very big bosses—return their calls and their emails on a regular basis. The others were arrogant, lazy, or both—and that’s how they are likely to be remembered at tribute time, silently or spoken.

I’m not sure when this sort of behavior became acceptable. It probably had something to do with email, to the people who are facing 200 or 300 entries in their inbox every day. Often those people have an assistant to help them manage the flow, but it is up to each person to decide whether the words “I’ll get back to you” mean something or are hollow.

If you don’t want to read someone’s business plan, say so. I do it all the time. Say “that’s not in my wheelhouse” or “my plate is too full at the moment” or” I don’t think we’d make good partners.” That’s honest and takes you off the hook. Anyone would rather hear that than the sound of silence.

If you agree to get back to someone, or you solicit candidates for an open position, you should follow through. That is the right thing to do, and guess what, someday you too will be on the sending end of that interchange, and you’ll wonder why the other person has decided not to let you know the truth. People I know right now who never returned phone calls aren’t getting their phone calls returned. How about that!

I have seen this work both ways at every company I have worked, partnered, or consulted. All of the great CEOs and Board Members for whom I worked returned their outside calls and emails, especially if they asked to see something. The best VCs I know let you know if they want to proceed or not—they don’t all do this, but the best ones with the best names do. Realtors who want a relationship with you call back whether you are a seller or a buyer, whether you have a listing or are even in the market. Most of the mayors of great cities respond to the feedback they solicit. So do the Senators, House Representatives, County Supervisors, and Assembly Members.

You know who doesn’t return your call? The guy who sat in the cube next to you when you were 25 and now is a VP at the ZYX company, the guy you later bump into at Starbucks and says give me a call sometime, and when you do, doesn’t acknowledge your call. Rent his office now, he’s toast. You know who else? The person who fashions herself a boutique investment banker, whom you meet at a networking event, who asks if you know any great start-up entrepreneurs, and when you send one her way, ignores them. Wouldn’t give her my business. Anyone else? The op-ed executive at the dying newspaper who doesn’t tell you why you didn’t make the masthead. Also that fellow in your LinkedIn Level 1 contacts who says in his news feed he has an open position, and when you forward him a friend’s profile, never clicks on it.

Here’s the cool part, where the winners really win. The truly resilient never hear the sound of silence. If you ignore them, they go to the next person, and the next person after that. Who loses? You do, my former friend, because the individual who is that resilient, who does not care that you did not respect him, that is the person who probably has the best idea in town. Know what? You could have had it first. You asked or agreed to review it, but then you dropped the ball. When that resilient person finds the right partner, she has won, you have lost. Every single time.

You are always better off being honest with bad news than silent with none. If you only respond when there is good news—something you want or need—you’re opportunistic, not in it for the long haul, surely not someone who cares about the people in your circles, only what they can do for you. When you open a door, open it all the way, or your true intentions will be impossible to hide.

Your network is only valuable if you nurture it constantly. Your word is all you have.