Absolutely yes! Whilst it IS true that some people have had awful run through no fault of their own, the lack of vision is the killer for most people. I had my epiphany moment a while back as to where I wanted to go and what I wanted to do, whereas before I'd just went through life on a stream of making ends meet and never thinking beyond that, wondering why things weren't looking up and why opportunities weren't coming my way. A plan and a vision does wonders for self esteem and your drive to succeed, instead of never thinking beyond your next sum of cash.
You are right! There certainly is "bad luck" out there, like the ecletricity-cut that prevented me from posting this a few hours earlier :D. But things like that rarely happen. The biggest problem is as you said, the lack of vision. Sometimes we dont even realize that there could be much more in life. That's even more so, if we start to excuse own faults with unlucky fate.