The icons were copied (with permission) from those used on bench-marks.org.uk, then mapped onto
the loggable condition options available on trigpointing.uk (though BMD have since introduced extra colours to eg discriminate between "probably destroyed" and "couldn't find it").
I'm personally not sure what the difference is between "probably destroyed" and "couldn't find it", as it seems to depend on the visitor's self confidence. Similarly, one person's trig that's been slightly damaged by fixing a birdbath on top, is another person's trig that's been converted into a birdbath. And when does a toppled or removed trig become remains?
On a PC with a mouse, you can just hover over the icon to get the full text of the logged condition. That's not really possible on a mobile. But then again a mobile has limited screen area, so icons would ideally be better than text (assuming they're easily understood!).
What're you suggesting for a better UX? I could add a full text description after every icon (though I'd want to make that a user preference, because personally I prefer icons). Or I could match the BMD approach, and add various additional shades of blue / mauve icons, to distinguish couldn't find vs missing, inaccessible vs unknown, etc? (But IMHO that'll make it more unfriendly to casual users, who might instinctively understand that Grey/Red is the grey area between maybe destroyed and destroyed, but might not immediately twig the difference between navy blue and mauve). Or something else entirely?
I'm definitely open to suggestions!