- is this your decision to make in the first place?
- have you even accurately defined the decision you are making?
- did you think about all the possibilities?
- did you weigh all the facts available? Listen to all viewpoints? Ask a trusted friend?
- did you make the decision with the appropriate timeliness? Is there more time to wait and see? Or would that make it worse because the time to act is _now_?
- are you operating out of fear, anxiety or are you calmly reasoning with logic?
- conversely learn when it is appropriate to "trust your gut" - this is especially appropriate for emotional decisions (should I adopt this dog?). And when it is not (I really love this car/house but it's too much $$$$).
A bad decision is where you did badly on stuff like that. If a "bad" decision yields a good result, sure take it, but realize that was just dumb luck and don't push it - it was still a bad decision.
If it was a "good" decision but had a bad outcome, you must separate the disappointment and consequences, which are still real, from any guilt related to "making a bad decision". Most of us did stupid stuff when we were young. The anger at yourself for doing something so dumb is usually the worst punishment. Avoid doing stupid stuff.
Over time you learn and get better. You will rarely give yourself a perfect grade in all categories. Regardless of outcome, think about what you could do better. Perhaps your weighing of one fact over another was not ideal. You focused too much on a minor consideration and did not grasp the weight of another consideration? OK, learn from that too.
"Helpful" and "Sympathetic" people will like to try to come by after the fact and say "what, you didn't consider X - it's obvious?" or "You should've just done Y" (no shit, Sherlock). But hindsight is 20/20. It wasn't their decision to make. It was a good decision based on ...
It should be noted that good decision making process is composed of many small decisions (which fact should I focus on?, is this the right time?, who should I ask?), etc.
It's decisions all the way down until it's either the bedrock of fact or else the unknowable possibility.
