If you want to succeed as an entrepreneur, says Seth Kaufman, psy.d, , Certified Career and Life Purpose Coach for the Think Human, you need to “marry purpose with what people want to purchase.” This pithy expression contains some important entrepreneurial advice.

Dr. Kaufman says you need to have a strong idea of what you want to do, and a strong passion. But you also need to make sure that it’s something others are interested in buying. “Do your research,” the career coach says. “Do your homework.” You can do polls and surveys to find out if people are really interested in buying your product, or if it’s best just staying in the realm of a proposed idea.

The “biggest mistake” entrepreneurs make, Dr. Kaufman says, is having a great idea and not grounding it in what people would actually purchase. He explains that entrepreneurs need to aim for the “sweet spot” – something they would be excited about, melded with what others would want to buy.

He also notes that money isn’t as much of a motivating factor for entrepreneurs as you would think. People who do things just to make more money “run out of steam,” Dr. Kaufman says. It takes more to motivate, like a belief in the product.

The career coach says that if you don’t give off genuine excitement, your venture just won’t work.

“True authenticity sells,” Kaufman says. And the nice thing about it is that it fits with your personal fulfillment, notes the coach, providing a paycheck as well as a purpose.

The Think Human offers life, career, entrepreneur and executive coaching services.