Finger pointers and peak-level bullshitters have mastered the art of denial to shield themselves from criticism and their shortcomings.
What they can't shield themselves from is the barriers they build when they refuse to accept responsibility for their actions and outcomes.
Underachievers fail to realize that nobody gets it right all the time. But the smart ones understand that learning from failures is where the most growth takes place. What they tried wasn't working, and if they can swallow their pride and be humble, refusing to make unwarranted excuses, they're the ones who will live the best lives. They will make changes, try a new approach, and much of the time, they'll find a way to succeed.
In doing so, they'll fuel the excuses of those who are falling further behind on their way to a very mediocre life.