This is a fab example for why it’s so important to test logos in different applications and to look at them from a variety of perspectives.
During the concept phase, one approach is to take the letters of the brand (if that’s the kind of logo you are developing) and writing them down in every possible way you can think of to see if some magic happens and they reveal a visual characteristic that translates well into an icon or shape.
It seems the creators of this icon did go some way with that and once you look at it the intended way you can see the minus and plus in the letters – but it’s a real pity it has an upside down side effect that’s rather confusing!
In any case, it’s worth a smile and made my day!!!