This is interesting. A new line of research suggests that each day the brain gets drained quicker than we think.
Like a muscle, overusing our brain on one decision (what to eat for lunch) weakens our ability on other things that happen later (test questions in an afternoon chemistry test). Debating the lunch decision too much may mean missing more questions on the test.
From the article…
Indeed, University of Maryland psychologist Anastasiya Pocheptsova and colleagues found exactly this effect: individuals who had to regulate their attention—which requires executive control—made significantly different choices than people who did not. These different choices follow a very specific pattern: they become reliant on more a more simplistic, and often inferior, thought process, and can thus fall prey to perceptual decoys. For example, in one experiment participants who were asked to ignore interesting subtitles in an otherwise boring film clip were much more likely to choose an option that stood next to a clearly inferior “decoy”—an option that was similar to one of the good choices, but was obviously not quite as good—than participants who watched the same clip but were not asked to ignore anything. Presumably, trying to control one’s attention and to ignore an interesting cue exhausted the limited resource of the executive functions, making it significantly more difficult to ignore the existence of the otherwise irrelevant inferior decoy. Subjects with overtaxed brains made worse decisions.