The statistics speak for themselves: 50 million records sold, 14 UK No. 1 singles, and almost every one a blossoming, beefy love song delivered by a group of serious young men sitting in a line. Westlife's recipe for a perfect pop song may be simple—start quiet, get bigger, become enormous, change key, and retire—but their songs have soundtracked countless first kisses, engagement videos, and wedding dances.