I think the lack of response to this thread answers your question.
A lack of diligent business planning.
Read the posts on this forum. Plenty of people wanting free advice to get them up to speed, but no real discussion.
Basically, too many people are trying to make a quick buck in an industry they do not understand. Some basic queestions people could consider are:
1. What will my customers expect?
2. How much will it cost me to provide it?
3. How much will customers pay for it?
4. How will I find my customers?
5. How much will it cost me to find my customers?
6. How much will it cost me to retain my customers?
7. So, will I make a profit?