The biggest key to success in any company or business is to solve a problem. As they say, necessity is the mother of invention. If you can know a problem that a certain segment of a market is having and also have figured out a unique way to solve the problem then you are halfway to success.
This is why starting a SaaS business is one of the best ways to make a lot of money and potentially very quickly at that. People need their problems to be solved in an easy way and will gladly pay money. If you create software that does this for them then you can even be making money in your sleep.