I'm not a fan of his, but Michael Jackson's "Thriller" changed the music industry. It had something like 7 top 10 singles, so I think the record companies realized they could save the cost of an artist recording an album a year and instead bleed an album dry of singles for 3 or 4 years. It was a cultural force, coming on the heels of MTV and dominating the airwaves. I wasn't too happy about much of it, but good product or no, it changed the way music was delivered. I think that mentality killed a lot of bands, too. Instead of pumping out new product, which kept the original release fresh, the companies took successful albums and wrung them for all they could, basically oversaturating it to the point that no one wanted to hear the follow-up.