^^ I believe it was the enormous pressure and expectations. The nerves seemed to lead him to forgetting his 3-axel technique, plus he didn't make an effort to go for the quad at all. Perhaps the quad was not solidly under his belt. But if you nix doing that element you planned all year to be competitive, then skating cleanly is crucial.
On the positive side, all disappointing experiences are redemptive if there are lessons one can learn and apply. Failure is not the end of the world; look up quotes about failure and you will find a treasure trove of great wisdom. Yes, time and opportunity are limited in figure skating, but sport is not an island within itself (meaning use what you learn to go forward in life and in figure skating if Adam desires to continue with skating, and I hope he does).