There are three main mantras:
1. Nobody is perfect.
2. Don't make the same mistake twice.
3. Life is iterative.
We're all human, we all make mistakes. How you deal with mistakes and problems, is what really elevates successful people, robotics teams, organizations, etc above the rest.
Whenever you finish any major project, you should always sit back and reflect upon what you did good, and what could be done better. Be honest with yourself - if something was terrible, come to accept it. Don't blame other people/events/etc! It's way too easy to fall into a trap that "if only
X random event didn't occur, we would have won!", when you should be working on making yourself/your team immune to
X random event.
I personally tend to follow the "Toyota philosophy" that initial mistakes are the result of bad process - not necessarily bad people. Analyze what went wrong and what could have prevented it, then take action on implementing new ideas/processes to prevent the mistake from occurring again.
For a long time, the "what went wrong" will all likely revolve around lack of experience. The only cure for this is to keep getting back on the horse when you get kicked off. The more you practice, the more you do, the more you reflect on what you're doing, the better you get. It will take years and years (it has been referred to as the "
10,000 hours of deliberate practice"), but one day you'll look back and realize that you're no longer making all those mistakes that you once were.