I've been thinking of evaluating opportunities lately from the perspective of threats.
There's a downside to it, which is that focusing on the negative can mean a lowering of personal affect, morale, whatever. You tend to get more of what you focus on.
However, evaluating "what are the threats in the way of this succeeding?" seems like a pretty good way to check into ideas that are already on their ways towards correct execution. What could happen, with yourself, your team, competition, or other external stakeholders that could derail your success?
If you identify for threats, you can prepare against them. A cashflow crunch is easier to solve far in the future by securing some lines of credit during good times. If a key client or contract might be paid late, get that credit. If a single client accounts for more than half of your revenue, start diversifying even if it slows down your revenue growth. If a single sector is all you deal in, look if you can pick up a couple side-streams of revenue, especially covering most of your overhead.
Don't obsess over threats, and don't start thinking of them until you're well on your way -- by far the biggest risk is that your project never gets ignited and gets off the ground, and the you or your partners just don't hustle enough. But once things are going, do a once-over on threats. It could be the difference between success and failure. An ounce of prevention and all...
One of the more unfortunate things about people is the intersection of responding to incentives and recognition primarily, thinking short-term in time, and not reasoning through events that don't happen.
When an engineer or surveyor goes on and on about improving earthquake or hurricane measures, they're generally perceived as a nag, burden, and hassle -- until you get a bad hurricane or earthquake that costs lives, causes immense human misery, and does millions to billions of dollars in possibly preventable damage.
In business, you wind up with lots of these too. There's dozens of little things that only have a 1% chance of occurring, but the majority of people will perceive you as a hassle if you try to bring them up.
For instance, a friend of mine owns a large bilingual IT firm in a highly developed, non-English country.
At the advice of one of his mentors, he moved his salespeople's commission structure from the old system that was based just on revenues, to one that had "diversification" as a criteria. This was because his firm was doing most of their business with just a few very large clients, and they had immense leverage over his company. And if one of them should switch providers, they'd have gotten hit with a serious crunch, and potentially would have had to lay some of their excellent team that had taken many years to build.
If you want to totally screw up your life, here's my advice: cultivate some bad habits. That's how most people do it. Very few people screw up their lives by drinking once, but a lot of people screw it up by developing a drinking problem. I've never heard a story of someone who went to Vegas for the first time and lost his entire fortune, but I've heard plenty of stories of people with gambling addictions who have blackjacked their way to bankruptcy. Even breakups are far more likely to be caused by habitual bad behaviour than by a single action (even in the case of cheating, a lot of couples stay together).
This is because a single action doesn't have all that much leverage on your life. But habits, on the other hand, define us as people-- literally. What we do regularly becomes a label. Bob's an alcoholic. Tom is a cheater. Raymond is a gambler. Habits change ephemeral verbs (Tom cheated) to nouns. Once you're defined by your habits, it takes a lot to change that. If Bob doesn't drink for a night, he isn't magically changed into tee-totaler. You are your habits.
And that's why habits are my religion. I write about them all the time, from every single angle, and that's mostly a result of being fixated on habits in my own life. If you can change your habits, you can change who you are. So I pay very little attention to rare occurrences and work on my habits constantly.