This might be a bug/UI fix, but seems fairly trivial. I wanted to report it somewhere, so it's a known issue. One Windows 3.3.12, mouse over text for sort by is implemented in a very clever way: it shows current state and state if clicked. But if you mouse over the sort direction arrow, it says "Reverse sort order" regardless of the direction the arrow is pointing.
I suspect that the intent is to read "reverse" here as a verb - such that clicking the arrow will reverse whatever direction it is currently pointing. However, the phrase "reverse sort order" is often used as a descriptive phrase (with "reverse" as an adjective describing the sort order), which can create some confusion. From a UX design perspective, this is especially problematic since the element right next to the arrow shows current/future state on mouse over - completely different behavior. I do understand the arrow icon communicates the order - but the icon next to it also communicates the type of sorting.
Possibly the simplest fix would be to simply change the word "Reverse" to "Flip" - this would avoid any language confusion. Even better, IMO, would be implementing the same functionality as the sort type button and display current state/future state for UI consistency. Something like:
"A>Z -> Z>A" or "Asc -> Desc" Unfortunately, some apps interpret the arrow differently, so an arrow alone isn't always 100% clear.