Sometimes you kind of know a gadget is going to fail, simply because it launches at the wrong time. A great example would be the Microsoft SPOT watch which was essentially an expensive and ungainly data-casting wristwatch that could show very small amounts of news and weather data while you walked. Sounds OK, until you realise that it was launched at the same time as mobile phones were moving into data, as smartphones were appearing, as wifi was taking off.

The fact that even nerds had more fashion sense than to wander around with a pile of crap masquerading as a watch on their wrist probably didn't help either.

It just goes to prove that despite many millions of dollars spent in market research and product testing, even the biggest of companies can get things wrong. What's more, even good gadgets can end up with bad commercial results. The question, therefore, is why? Why is it that some gadgets can succeed while others fail despite great design? Why can't that company which has found great gadget success replicate it every single time?

These are the questions that Forrester Research has been addressing, and attempts to find the answers to, in a new report called "Cracking The Convenience Code" which argues that the big secret to this successful gadget development and marketing is wrapped up within a pretty small and simple concept: convenience.

Forrester has drawn upon a decade of consumer survey results, covering hundreds of products in order to develop what you might think of as an analytical framework for consumer product strategists to allow them to quantify a product's convenience (for which read ease-of-use) as far as the target consumer would be concerned. By applying this methodology to a number of consumer product markets such as home audio, video convergence, and mobile applications, Forrester reckons it has got a grip on the big why does a product fail question. More to the point, I guess, this means it also has a grip on the why do they succeed one as well.

Take the Amazon Kindle by way of example. This can be used to illustrate how Forrester uses the convenience framework to explain why somewhat awkward products (and the Kindle is certainly that) can still succeed and then some. "The Kindle's large, obtrusive buttons cause users to change pages randomly without intending to," writes Forrester analyst James McQuivey. "Yet the Kindle has blown past forecasts and created an entirely new market because of two specific kinds of convenience: convenient access to cheap digital books and wireless access to the bookstore from any location. Both of those things make owning a Kindle dramatically more convenient than buying books at Barnes & Noble and schlepping them around on planes. We can employ the Convenience Quotient to determine that the overall consumer product experience makes it a winner, specific flaws notwithstanding."