The tell of false attention is presupposition. If your focus is aimed only at where you 'suppose beforehand' the thing will appear, you are not attending — you are waiting, and blind to everything else. 'This attention to the preconceived is equivalent to being absorbed in one point of the visible area and not paying attention to the other points.' Expectation is a kind of blindness: the more certain you are of where the important thing will come from, the less you can actually see.

— In our words · Source: Meditations on Hunting (José Ortega y Gasset)