He was initially a 200-meter runner, and his coach wanted to have him run the 400. They made a bet that if Bolt broke the Jamaican 200-meter record at the national meet in 2007, he could run the 100 instead, and never have to do the 400. Bolt smashed the record of 19.86 with a 19.75 time. He never had to run the 400, and he added the 100 to his arsenal. He's gotten pretty damn good at it since.