Lots of research has been done into entrepreneurialism. We know that the Type-A personality is often not willing to take risks and may end up working for others their entire life, and that more C students become entrepreneurs than do A students.
The one lesson I have found most important is that of overcoming fear. It took me years to overcome my fears about losing my customers, having to make payrolls on time, or paying my bills on time. It took me awhile to realize that these things are probably going to happen from time to time no matter what.
No one has a crystal ball to tell us what is going to happen in the future. All we can do is to keep on keeping on and work on honing another universal trait of entrepreneurs: persistence. even in the face of challenging times.