Stop, look, and listen.

We teach it to our children, to keep them from harm. But as they become adults and rise to executive positions in technology companies, they fail to heed those words of wisdom time and again.

It’s what happened at Polaroid. It’s what happened at Digital Equipment Corporation, Compaq, and Kodak. We’ve been witnessing the failure of BlackBerry’s leaders to follow that advice for years.

Stop, look, and listen. It’s such a simple formula. It’ll keep you safe crossing a busy city street, and it can keep you in business, too.

Stop. Wonderful, you are kicking the competition’s hindside. Better yet, there isn’t any competition. You are dominating the market, and sales are accelerating. Nothing appears to stand in your way. In that case, you can afford to take a break—one day a month—from executing your world-conquering strategy. And stop.

Look. Get your head out of the sand of daily operations and look outside. What do you see? Not through your corner-office window but from a perch with a nice view of your customers. What are they doing with your product? How satisfied are they with the experience? Yes, your gadget is at the day’s cutting edge, but how else are your customers solving their problems? What alternatives do you see them turning to? Then look to your own imagination and demand that it give you a good look at the worst-case scenario of the future.

Listen. Put your ear to the ground. What do you hear? What do the Web whispers and blog rumors tell you? What do your old business-school classmates have to say? Remember that venture capitalist you met last year? Give her a call and ask what’s got her attention. Take everything you hear seriously. Catalog it and then ask your colleagues to listen to you.

It may often seem like dominating technology companies get blindsided—that they are toppled by stealth disruptive forces they could not have seen coming. It’s a great story line for Silicon Valley startups, but it’s almost never the truth. Instead, many leaders in high-performing companies fall so deeply in love with their success that they are unable to overcome their own cognitive blinders and they fail to react to market changes and new competitors barreling no more quickly or secretly than an Austin Powers steamroller.

One day a month, just stop, look, and listen. You’ve known it’s been good advice nearly all of your life. You’ve seen what happens when others don’t heed it. And one day it may just save the life of your company.