Despite the low-resolution screen, slow hard drives, very little RAM, and CPUs that were middling even in 2012, it’s an open secret among Apple employees that the “101” still sells surprisingly well — to a nearly tragic degree, given its age and mediocrity.
Geeks like me often wonder why anyone would still buy such an outdated machine. I’ve heard from many people who buy it (or who’ve been unsuccessful in talking others out of it), and it’s surprisingly compelling, especially for volume-buying, price-conscious customers such as schools and big businesses.
It still sells because it's cheap, can use cheap spinning hard drives (with large capacities), has a DVD drive, and performance is really not that far behind today’s current retina MacBook Pros. (That last one is on Intel’s shoulders.)
Personally, I really like retina displays, SSD storage reliability and performance, and I have zero interest in a DVD drive. But others do, though.