The pop culture taught us the drama of a button press. Be it a doorbell that the stranger rings on a rainy night, or a nuclear weapon being launched by the Army commander, the culminating moment happens when the button is pressed.
Which is why it was somewhat shocking for me to realize that with buttons on a computer screen, what triggers an action is not the moment the button is pressed, but the moment it is released. Once you press the button, you can still change your mind -- simply move the cursor away. This creates a very different kind of drama -- in a way a slightly diminished one, as we have one more chance to rethink what we're doing, but also a more suspenseful one, as the thing that now separates us from the action is a natural state -- a release of a button, the removal of a hand from the mouse key.