Comment by pixl97

Especially when you get outside of environment like phones and consoles the environments people run software in can be wildly different too, and the oddest things can cause weird interactions.

In enterprise software you can run into customers that 'use too much' of something odd that the developers don't really think about and QA fails to test right. Things like tags and identifiers that you think "Oh they'll use 5 or 6 max" then you run into someone that uses a thousand tags and report performance explodes.