In any kind of business, there is always risk involved. A business failure is not, actually, 100% because of poor management (though you can bet that there is mismanagement involved). Sometimes, it's because you're just unlucky to put up the wrong business at the wrong time at the wrong place or a subset of the given statement.
While poor customer turnout is already a problem, there will always be the case of misbehaving employees. By 'misbehaving', I mean employees who have perhaps forgotten that they are paid to work, not to lounge or to steal or do whatever misdeed. These are people who seem to have forgotten to read their books on business ethics. A comprehensive character check can prevent your company from being invaded with this kind of people. It's quite a waste of capital, I know, if every applicant is honest (that way you'll only evaluate their employment credentials) but, I guess, misbehavior is already part if human nature.
Another big headache when it comes to businesses, especially when you are into retailing, are the misbehaving "customers". Shoplifters, cheaters, and the like. It's really frustrating to contend with these people who do not realize that you're doing an honest job (you are, aren't you?), trying to make a clean business and here they are, stealing from you. This can be easily given a solution (well, not-so-easily) by installing a surveillance system all over your shop. This way erring individuals are caught.
One cannot help but think that, instead of surveillance systems, more useful items such as wall phones system can be bought, had it not been for these inconsiderate beings. It's a sentiment shared by generations and generations before us. As I've said, it's part of human nature.
Establishing a business is no easy task, but with know-how, a little bit of luck, and honest employees, I'm sure you'll do good.