They are afraid that their products and services will not have enough market to sustain the business. There are many good ideas out there. Believe it or not, clever product and service are dime a dozen. Most of us have at least one good idea, but these ideas often never get implemented. Studies in fact show that the lack of good idea is not necessarily the primary cause of the failure of many small businesses.
Businesses fail because of the entrepreneur's lack of preparedness.
Many entrepreneurs start a business, not because they have a business idea that can be profitable. Searching for new ideas and concepts is a formidable task. Some ideas spring forth, fully formed. Others simmer for years, waiting for the opportune moment. The business idea for you may lie in your previous work experience or your familiarity with the daily operations of a business.