“You cannot make progress with excuses.” –Cam Newton
You cannot improve if you believe you are perfect, nor can you deny your own culpability in your failures.
We can always say “I failed because they didn’t tell me what to study.”, but that is still shifting blame. Why didn’t you know what to study? It’s not like you showed up to the wrong test or that the subject changed radically over the weekend. YOU messed up.
I failed my black belt test. I was recovering from a broken leg, my ex dropped on me she was traveling for the month and a half before hand so I had additional parental duties, work got out of control. Doesn’t matter: I failed. I didn’t do enough work before and could have practiced smarter and better. My fault.
Accept responsibility and then you can get better, it is that simple and that brutal.