Psychologists Barry Schwartz and Adam Grant present a compelling argument that many psychological phenomena follow an inverted U shape, where an increase in a certain factor (X) initially leads to a rise in a desirable outcome (Y), but beyond a certain threshold, it results in diminishing returns or even negative effects. This suggests that while something may seem beneficial at first, too much of it can actually be detrimental.

This idea is echoed in Malcolm Gladwell's book "David and Goliath," where he suggests that no trait or experience can be considered entirely positive. Instead, even the most advantageous characteristics can have downsides that outweigh their benefits when taken to extremes, leading to a deeper understanding of the complexities in the relationship between various traits and outcomes.