What's the difference between breaking records and selling the most records in the music industry?

I don't understand the qution.... If your asking the differnece between being amazing and seliing the most ... You don't need to make amazing music to be the best... Gaga for example. Her new album is not the best to say the very least, but the name she made herslef in the industry allowed her to sell the most, along with breaking records as fasting selling album .