The quick answer is just because. It is impossible to tell how a web page is going to do, if it were easy we’d all be billionaires right? If you make 100 websites you may have one that’s a hit, then again you might not. You can make the best website in the world and if no one needs or wants to use it then it will fail. Here are a few reasons why websites fail.
If you don’t have a game plan, if you don’t have agreed upon goals then you are bound to fail. How can you succeed when you’ve not even defined success. Do you want to build and then sell, do you want to get 500 visitors a day, or 5,000 visitors a day? Look ahead and plan for future needs as well. If your site does well are you going to need a dedicated server, or to hire employees?
Having unrealistic expectations can make you give up quick. If you expect to be a millionaire after just a few months, or even years of working on a project then you might as well give up now. The odds are just stacked against you. Really. It will take years and thousands of hours of work, and there still is no guarantee. It’s a gamble you must be willing to take.
Webmaster Gives Up
Don’t give up. Keep focused keep moving forward, keep attempting to meet your goals no matter how many times you fail.
If you have no funding or backing you cannot afford to keep the site up.
You need some money to advertise and spread the word.
No Social Buzz
No social presence is a killer. They always say word of mouth is the best advertisement right?
No Back-link Generation
If sites do not link to your site, and you plan on relying on search engine traffic for visitors then you are in trouble.
Poor graphic design and layout will kill your site. Web 2.0 is in now. Maybe it will be 3.0 in the future.
If your program or cms doesn’t work then your project is dead in the water.
Over-saturated Niche Market
1 niche comes to mind ring-tones/mp3’s if you pick a market that has to much competition you are not going to succeed.
Webmasters Choose the Wrong Topic
Choosing something you are not interested in is a bad decision. If you don’t like what you are doing then you are not going to keep on doing it.