I remember at that time that the discounted Atari 800 was something like $400, then only a year and half later the discounted Atari 800 XL was $99. I was very happy to be able to afford these computers at the time, I didn't understand that this was the death knell.

I was annoyed at having to use a C64 for one of my first for pay projects, when the 800 XL was so much better as a development machine (yes the sound and graphics were better on the C64, but slow disk and lack of good OS ruined it for everything else). But they correctly deduced that the C64 would have more longevity so they chose it.