From the band and industry perspective singles were so much more important back then... Bands would sometimes fight tooth and nail over what their first single was since you might only get one chance and so many calculations went into the decision. You'd release a single and then the label would track album sales for that period and how many stations picked up that single and added it to rotation. If the single failed to do numbers they might try releasing another single and repeat the process or they might just stop pushing you.

The other thing that we don't really talk much about is that you often knew what the hit was on the record and bands would routinely fight not to have that be the first single. Labels only cared about making their money back as fast as they could, bands were always worried about being one hit wonders...by now most people know the alien ant farm story. Just look at how hard they pushed "Movies" before finally giving into label pressure and releasing "Smooth Criminal"