By changing the way music sales were counted, SoundScan changed the way music was sold. It established a clear and transparent way to count sales that couldn’t easily be gamed by stores, which in turn changed the practice of tabulating sales “from a subjective methodology to an objective methodology,” says Jim Caparro, former president of Polygram Group Distribution.
Source: How SoundScan Changed Music, Driving Metal, Rap and Alt-Rock Up the Charts