This is something that One Direction member Louis Tomlinson quickly learned during a performance in the Welsh town of Cardiff this week.
Launching into a cover of cult 2000-era tune "Teenage Dirtbag" by Wheatus, the group was supported by their usual soundtrack of screaming fans until one very poignant moment when it was Louis' turn to take the solo.
After mumbling his way through the first few lines, the teen heartthrob decided to give up and admit defeat.
"Okay, I just forgot the lyrics. I'm not even going to pretend I know them," he announced.
However with the support of the crowd and his band mates, Louis quickly picked the song back up, celebrating a brief moment of triumph by pumping his fist in the air and shouting, "Yeah!"
He later apologised for the slip-up with a humble, "Sorry, Cardiff," as band mate Zayn walked over and patted him on the back.
Even when they screw up, they're still so damned cute. What is up with that?