As a firmware engineer, my philosophy is this: if I'm doing my job properly, the user should never even know I exist.

Maybe this isn't applicable to all software devs. If you make web apps, users actually see your UI, they click an icon or type in a URL and hit enter with the intent of using the thing you made. With firmware, that's not how it works.

When you hit the "mute" button on your laptop keyboard, it should just do it. The audio should turn off and the little LED should light up. If that fails, even once, the mirage is broken. The user is forced to think about the fallibility of firmware, which is a word they might not even know, and still struggle to conceptualize if they do. I think it also has a lasting effect on the way someone thinks about the pruduct: Is this going to work today? Why did that happen? Was that a virus? So on.

OTA firmware updates have the same problem. Most users don't know what the hell firmware is. All they know is their computer is showing a loading screen they've never seen before. It's unfamiliar and weird.

Like I said, I don't know if this mindset translates perfectly to other fields, but the priorities that fall out of my philosophy certainly apply. Reliability over everything, and get it right the first time.