New Real Madrid coach Alvaro Arbeloa said his shock debut Copa del Rey last 16 defeat at second-tier Albacete had to make the team better.
Arbeloa replaced Xabi Alonso at the helm on Monday after Madrid were beaten by rivals Barcelona in the Spanish Super Cup final.
"I'm not afraid of failure, I can understand that someone would want to call this defeat that," Arbeloa told reporters.
"If I have learned anything in life it's that failure is on the path to success, for me they are not in opposite directions.
"This is something that will make me improve, and it has to make everyone better."
Former Madrid and Liverpool defender Arbeloa, promoted from his role as reserve team coach, remembered he suffered similar cup knockouts in his playing career.
"I have failed many times in life, I suffered tough eliminations in the cup, even worse than this," he continued.
"With all the enthusiasm in the world I'll get back tomorrow to Valdebebas (the club's training ground) to work with my players and prepare for Saturday's game as well as possible, so we do things much better than today."
Real Madrid host Levante at the Santiago Bernabeu on Saturday as they try to cut down Barcelona's four-point lead at the top of La Liga.