In business school, my professors hammered into us that all marketing plans must include the Four Ps of Marketing (product, price, promotion, and physical distribution). Those Four Ps were treated with nearly as much reverence as the Ten Commandments were by the Sunday school teachers of my youth.

I came out of business school knowing that breaking one of those Four Ps would send me to corporate purgatory at the least and perhaps to corporate hell.

But as with most things in life, being taught the mechanics of something isn't the same as experiencing it first-hand. And what I've come to realize about the Four Ps is that they are like the four fingers of your hand trying to work without the fifth digit on the end-something's definitely missing. Most marketing plans based upon the Four Ps, don't accomplish the desired results because they are missing the fifth P, the sizzle with the steak, passion.

Now I realize that the word "passion" conjures up ideas about love and commitment-the kind of soft stuff that I usually don't spend much time writing about. In fact, you might be asking yourself this very moment,"Self, what's happened to Mark? Has his kinder, gentler side taken over? Or, isn't his elevator going all the way to the top anymore?"

Well, have no fear; I'm still the same burly, opinionated, politically incorrect guy you've come to know. I've simply learned that if you're going to be good at getting customers to believe in your products or services, you have to love those products or services yourself. I've seen that in order to excel at marketing, you have to love what you do and have real passion about it. It's like a relationship: If there's no flame in it, it ain't gonna last.

Some people think that exhibiting passion is corny or that it's a sign of weakness to show emotion. They are dead wrong, because customers can sense whether you have a heart-felt conviction about your products or services. If you can't be empathic toward your customers and don't have deep-seated feelings about the ability of your products or services to solve their problems exceptionally well, then fear and doubt will come through in your marketing.

I know that I'm right about most marketing plans missing passion, because I could only come up with a handful of examples of plans driven by passion. Think about it: When was the last time that you, as a consumer, were moved to action by a marketing campaign? How often do you get really passionate about something because you feel the passion of the offering? Not nearly often enough.

Unless you have Andersen windows in your home. Andersen Corporation started as a family lumber company in 1903 in Hudson, Wisconsin; today, it's known across the country for having the best windows and patio doors. Andersen employees, distributors, and contractors share a passion for quality, and it's obvious in their workmanship and service. As a result, customers see them as the best in the industry, the standard bearer.

And think about BMW. You'd have to be practically comatose not to get revved up about their vehicles after watching one of their commercials. BMW's passion for quality design is evident, and it transfers into their marketing. They understand that people love their cars! One can believe that a BMW really is "the ultimate driving machine," and that driving one isn't just driving a car, it's an experience. The company advertises its new Sports Activity Vehicle as "the SAV with a racecar complex." How's that for passion?

The Coca-Cola Company doesn't just produce and sell bottled drinks; it "exists to benefit and refresh everyone it touches." That's pretty passionate, and has resulted in worldwide brand recognition and loyalty. Coke has become part of our culture. In 1929, it was "the pause that refreshes." And remember the "hilltop" ad in 1971 that featured the song "I'd Like To Buy the World a Coke"? Or later in the '70s, when we had a Coke and a smile? More recently, we believed that "life tastes good" when we're drinking a Coke. The company's passion about its products transfers through its marketing and is shared by its consumers. I know many people who are fiercely passionate about Coke, and would rather be thirsty than drink a Pepsi.

And take a look at Ralph Lauren, whose brand is also part of the American culture. Lauren doesn't design all of his products anymore, but you wouldn't know it. He has the unusual ability to bring together the disparate talents of designers, art directors, writers, and producers to rally around his vision. His passion emanates through everything the company does, markets, and sells.

Windows, clothing, cars, and soft drinks are tangible products, but passion is perhaps even more necessary for marketing the intangible. Someone who does a pretty good job of that is Dr. Robert A. Schuller, known for his Hour of Power on Sunday morning television, broadcast from the Crystal Cathedral in Garden Grove, California.

Schuller began preaching nearly 50 years ago by renting a drive-in theater and conducting Sunday services from the roof of the snack bar. But his dream, according to his Web site, was "to build a great church for God, a church that would change and save lives, a church dedicated to the creed, 'Find a need and fill it, find a hurt and heal it.'" Thanks in large part to his passion for this dream, his congregation now has 10,000 members who attend services in the 12-story cathedral, which is recognized around the world.

Businesses can learn a lot from these leaders, who have a passion and fascination with marketing that's lacking in many businesses. It's not something that can be analyzed backward and forward, it's something that comes from inside. Like I said before, passionate marketing is like falling in love. It's a crazy obsession with your product or service and your customers.

Recently, Lance Armstrong, who won his sixth Tour de France cycling race this summer, was interviewed on television. The commentator asked why he continued to race when he had nothing more to prove and it required such sacrifice. "I absolutely love cycling," Armstrong said. "I can't imagine not cycling and not winning. I have tremendous passion for it."