Entrepreneurs are so used to the advice that they need a USP--unique selling proposition--for their products that it's a wonder they don't mutter the phrase in their sleep. But a study from researchers at the University of Warwick and Glasgow Caledonian University London, which appeared in a recent issue of Psychology & Marketing, suggests that being different may not be everything it's cracked up to be. Or, at least, when you look for a USP, be careful about just how unique you try to be.

The theory behind the USP is that if your product is a complete copy of a competitor, you offer customers no intrinsic reason to choose your offering over a competitor's. And that seems to make sense, so far as it goes.

But too much differentiation can ultimately cause a problem. At a certain point, too many market choices leaves consumers confused. There was a famous study from researchers at Columbia and Stanford in which a wider variety of product choices could be demotivating, with a net result of fewer total purchases.

Similarities Breed Confidence

Professors Qing Wang of Warwick and Paurav Shukla of Glasgow Caledonian found that, at least when it comes to cell phones, when competing branded products appeared similar, consumers had greater confidence in their choices.

The results took the researchers by surprise. They had expected the similarities to have a negative effect because the greater difficulty in telling the products apart would force people to--heavens!--have to think more, with resulting confusions.

However, that wasn't at all what happened. Instead, as was true with the Columbia and Stanford study, having too many choices resulted in what is called choice overload. (To get a sense of why this might happen, go into a large grocery store and stop at any type of product where the options seem endless.)

The researchers found what Apple and Samsung had likely expected: similarly can help transfer choice confidence from one brand (Apple iPad) to the other (Samsung Galaxy). That's probably why Apple pulled out all the legal stops, because it feared that the result could be losing potential customers to Samsung.

So, while you want enough of a difference to offer customers a reason to buy your product, there may be a lot to be said for emulating a category leader to help put to rest people's concerns about buying something "different."