If you build it, they will come is a fallacy. I know it. I have built several products that have bombed. My latest flop is an HTML to PDF conversion API called PDFMark.The pundits and coaches say you should always do your market research before writing a single line of code. And I think I have done market research. I had once built a cloud-based photo backup application after surveying existing users of my photo watermarking application. Many of them said they would use a cloud-based photo backup application. I had thousands of photographers using my photo watermarking tool and they were the obvious target users of a photo backup tool. Yet hardly anyone signed up for the product. When I conducted a survey and I asked them if photo backup was a problem and if they would use a cloud backup service they said yes, but when it actually came to signing up for the service and shelling out real money, not many people did.I am lost as to what do I even ask the prospective customers anymore? Henry Ford said if I had asked customers what do they want they would have said a faster horse. I am confused about the whole market research business.New trend on Twitter is about building a community before you build a product. I have followed several community builders. And I quickly realised, people who have thousands of followers are mostly good at gaining more followers. Those who are building real products have no time to post 20 times a day to build a Twitter following.When I look back, I realise that many of the products I have built simply because I thought building them would be cool. My most successful product – the photo watermark software uMark ($4K monthly) is one such product. I had built it because I thought it would be cool to build. I had no use of that product myself, I did not ask anyone if they needed such a product, I did not check if there was anything available in the market already. I did not waste time thinking a name or designing a logo. The first version was built over a weekend and released on a free download site. It got 1500 downloads on the first day.I really don’t know if market research and community building and all that is as important as it is made out to be. After that first product I have had no such luck with any other products.What do you guys think? What kind of market research did you do before launching? How did you decide which product to build?