Lack of Planning and Market Research
According to recent research most startups fail because they are providing a service or product which no one needs, or is dominated by a massive competition. This is because of lack of Planning and Market Research. You have to go out there and do proper surveys and talk to experts and analyze the competition. You need to have a step by step goal oriented blueprint for what you want to achieve through the business, it comes to notice that many startups have excellent Ideas and excellent service or product. but fail because of lack of proper planning; Pets.com was startup launched in August 1998, and failed terribly after 2 years, because it was ahead of its time. You might have heard to old saying "An Idea before its time is worse than a bad idea", with proper planning and Market Research this wouldn't have happened.