I find that the difference between a successful man is not what he does when he succeeds, but what he does when he fails.
I hear a lot of people all the time talk about their wants and dreams, and just as many will come up with some reason why they cannot be. They'll usually blame something else, like a coworker, a friend, an enemy, their personality, their past, or just society in general. Something will stand in their way that is out of their control and their first thought is that, as it is out of my control there must be nothing I can do about it. But that is one of the most, in my opinion, untrue and dangerous propositions one can tell themselves.
A problem should always be seen as an obstacle, not a dead end, even if the obstacle is yourself. Regardless of what is causing the situation, you need to assess three things.
1. Can the source of the obstacle be removed, and if so how hard would it be to do that?
2. Can the obstacle be worked around, and if so how hard would it be to do that?
3. Can I do something else, and if so how hard would it be to do that?
The answer to any of these should never be "No", you should never entirely disregard an option, even if you can't think of it right away. You need to think about it, you need to start thinking about options that aren't necessarily the BEST option, that is you may find that you can circumnavigate the obstacle, but in order to do so you have to sacrifice something, whether it be time or money or pleasure or something. These solutions shouldn't be ruled out, instead you should figure out what you have to sacrifice and whether sacrificing that is worth circumnavigating the obstacle. But you should think of all solutions, I can tell you with absolute confidence almost NO problem in the world will have the answer as "No" for one or two. And absolutely no problem in the word will have "No" as all three. If you find yourself seeing no solution for 1 and 2, it's more than likely you haven't thought about it long enough or in a constructive enough way, and you should go back to the drawing board and think about all your options. If you see no solution for all three, then it is certain you've not thought hard enough or constructive enough.
Life is a series of challenges and what makes a man successful is what he does when he is faced with adversity, what he does when something goes wrong, you should never see it as a dead end, it's a challenge, it's an obstacle and it's almost certainly one you can overcome.
Another thing is people are obsessed with rules and they feel that if the rules of a system tell them they can't do something, then they can't do it. For example, say you wanted to enroll in a course in university but you didn't have the marks for that course. A lot of people give up and don't pursue further, but you shouldn't do this! All that's happened is that probability of you getting into the course is no longer 100%, it's now not certain if you'll get into the course, but it's definitely not impossible! You need to talk to the people who make that decision, those people are people, there is a chance that they will let you into the course if you make a good enough argument as to why you should get in. Don't just read what's on the paper, think about how you can attack your obstacle, even if it goes outside of the rules on the document. There is one exception, the law is the only document you should stay within, attack your obstacle without breaking the law, but you may be able to break other rules like the course example.