Sometimes peoples' first startups are successful. More power to them. I've been pretty lucky, but not that lucky.
I had a bunch of startup failure before success. But that was OK because I was in a startup career path, which enabled me to think a bit more long-term.
In a startup career path, failure becomes experience for the next startup, which unfortunately will probably also fail. Repeat until success. And then repeat some more.
Of course many people never get a hit, and that is the harsh reality of the startup career. However, if you approach your startup life from the one and done mentality, I think your chances are much lower, if for no other reason than you have less chances.
Yet there is more to thinking of startups as a career than rationalizing failure. If you consider you're going to be doing this line of work for 20 years or more, it makes sense to invest in skills and relationships that may payout later.
If you don't know much tech stuff, maybe you should take the time to learn some now. If you don't know any investors or members of the startup press, maybe you should get out there and start meeting them. Whereas in the one and done mentality you can't be distracted by that long-term stuff because this is your only chance and every hour needs to be spent on critical path.
There are dangers in thinking this way though. For one, it becomes easier to give up and move on to the next project because you know there will be next projects. I've made that mistake.
You can also get too distracted on learning new stuff and never actually get anything done. Luckily, I haven't made that one. You have to strike a good balance between critical path and long-term stuff. I try to use that stuff as fuel to avoid burnout.
Perhaps most importantly though, thinking about startups as a career makes it easier to really commit. It's too easy to half-ass it if you are going to do one and be done with it. There are just too many fall-backs, and you can fall into traps that kill your startup from the inside.
If you're on the startup career path though, this is it. You become a real member of the small startup community, and are, at least in my book, immediately respected for drawing that line in the sand.
Update: some good comments on HN.