While there could be a better option, I don’t think a minus sign would have been an improvement. It is too close to the plus, with the only difference being the small nubbins on the top and bottom. The x, being rotated forty-five degrees, is distinctly different than the plus sign. That, in combination with the different bounding shape, provides ultimate contrast. Minus signs are also traditionally used for do-not-enter, don’t-do, or unavailable.

posted by Wade Preston Shearer on Thursday, Aug 19, 2010