Reasons for scarcity of working TI-58C machines

[SteveC]

The TI build quality of the 58C generation was not as durable as some others in my experience I had a TI 58-C in high school. It lasted through my senior year of HS and then 1 year of college. It just stopped powering up. My brother's 58C lasted maybe a semester longer. I discovered HP calculators were much more durable several purchases and a field of study change later. I have my second HP from the mid 80s (A US made 12C) and it still works for daily use. I did wear out the 10B that was my first HP. Few electric powered technologies have that durability.