Once upon a time..
HP made printers that were just TANKS. The HP III Laser? Where I used to work we had one that did hundreds of thousands of copies and just kept going. We even did double-sided printing (in a single sided printer) by just taking the paper that came out, turning it over and putting it back in the paper tray. (Yes, we had special software that printed the pages in reverse order on the back side.) It worked perfectly and gave very little trouble if you'd just keep it clean.
Where I work now, we have a bunch of ancient 9040n printers that just keep chugging along doing hundreds of pages a day. They break down once in a while, but occasional, simple repairs heave kept them going year after year.
Back in the day, HP sure knew how to build great printers.