[pmcp]

The use of icons lies not in understanding it the first time, it’s something that you learn to recognise. And that makes them more recognisable at the long term, or easier to find in moments when speed is of the essence. Like your example of the train. A conductor learned what they meant and trained with them. Just like a dj knows what every icon on his dj table means.

That also means icons don’t have to make sense visually, they just need to be recognised and distinguished.

Text is for when you have time or no idea, icons are for when you have to decide quick and you understand what you are doing.

[belugacat]

In the case of the interface shown in the train video, the key thing the operator will rely on is the fixed physical position of the controls first, then their shape, dimension, and color.

The icons really aren’t going to matter as much. And I’d argue they’d probably be better off replaced by text labels. Imagine a new operator in a stressful situation being guided eg on the phone - how would you describe to them which of the 2 buttons with a center arrow with a curve to their right they should press, for the control panel at 4:31? You’ll end up saying “the center left/right button”, or “the one above the green P button” because those icons are pretty hard to distinguish.

Swap the icons between 2 controls one day, and watch even the most skilled operator make mistakes.

[xp84]

> easier to find in moments when speed is of the essence

This is, for me, categorically untrue, it's quite the opposite. I am sure it must vary from person to person. I find myself wondering whether people tolerate or like icons-only because they would find the actual reading of an array of text buttons fatiguing. I'm not better than someone who finds reading more time consuming or difficult than I do, but I do kind of resent that UIs appear to be designed to cater to the less literate, because of how slow it is for me to pick the correct icon out of 7 very similar ones.

It's especially bad because these should just be preferences. Give me text and lose the icons altogether. Others should be free to have icons.