Hotcorner misbehavior

When I set different function of each corner. For example, I set left-down corner as show windows, and the right-down corner as show work spaces. When I touch the left-down at first, then there will a line of windows in the screen. But if I don't choose any one of them, touch the right corner directly. Then I find that there will be problem, which shows that the selection of workspaces will be kept there. I think maybe if after touching one corner, even do nothing and touch another corner, you should set a action of the first corner at first, e.g back to previous screen.