I disagree with the author. Handicaps are real, very real, they are not mere excuses to protect our sense of self-worth. If anything, what the handicapped/troubled person desires is to lift and be free his burden - and not to use it to fail repeatedly.
Apart from that, yes subconscious fear of failing, of being not good enough, can paralyze you and demolish your productivity. You spend time searching for that perfect design, then you stumble upon someone's else work, feel inferior/get jealous - go back to the drawing board, and your project gets never completed, not even halfway done. You can never be perfect enough.
So, striving for perfection is not a good ally, striving for providing solutions is.
But please keep real problems/issues out of that, you don't have the right to insult troubled people and call them under performers, and diminish their burdens to "excuses for failure".