"The last time I was at an awards show [before the VMAs] I was booed," RBMG/Def Jam's Justin Bieber told Jimmy Fallon of what was going through his mind in that much-discussed teary moment at the VMAs. Among other factors motivating his emotional response after performing new smash "What Do You Mean?" was the outpouring of support from the audience he says.

Bieber is clear-eyed and rueful about his notorious past misbehavior in this segment, and clearly focused on making music he believes in and avoiding the "knuckleheads" who encouraged his excesses.

Bieber then took to the stage for a confident rendition of his banger "What Do You Mean?" backed by The Roots.

In another segment, he discussed his prior hit, Where Are U Now," and offered a creditable country-style vocal version. Finally, in a nod to Fallon's propensity for musical fun, Bieber engaged in a rematch drum-off with Questlove—and acquitted himself quite well.