The iPod was already massively popular when the iTunes store was established. And more significantly, the store’s DRM didn’t prevent anyone from loading their iPod with music from other sources, legal or otherwise.

The iPod was even more popular by the time the 2D colored ads were introduced. There’s no denying that Apple’s marketing is next-level, and plays a huge role in their success, but it’s one of many factors. The iPod simply had better UI, a higher storage capacity, and tighter software integration than any other player available at the time.

It was also a great way to put all your downloaded music onto a single device, rather than burning it onto dozens of CDRs.

The fact that putting all your downloaded music on a single device was a lot easier and more convenient than burning it onto dozens of CDs certainly didn’t HURT its popularity. Nor did the fact that once you purchased an iPod, you could fill it with music without ever purchasing another CD.

The Institute for Scientific Proof of Really Obvious Things is doing great work. God speed.