Its about musical production. This isn't the first time someone has done analysis of timing in modern music. I think I first saw an article on slashdot in around 2010.

Recording "live" can be hard. it requires a bigger studio, more equipment, better engineers and crucially, everyone to be there at the same time.

you can, if you have a click track, record everything separately, and then marry it up later. once you have the drums lined up, you can just replay the tracks you have without the click track.

this means that you can record separately, at different times, in different locations. or if its your bedroom, you can move stuff around to the microphone you have.

But if you record a track as parts, you can then edit it. You want it to sound good right? laptop power has increased significantly, so any plugin can be run in realtime on multiple tracks.

SOme music suits it, others doesn't.

I _love_ the sound of a live band who are playing well. I don't love the sound of a live band who aren't.

Its hard to play together well all the time, so click track gives you a better bang for buck.