The Forbidden Toy is the classic. Google scholar on "forbidden toy" provides more on the subject, with elaboration and alternate hypothesis testing and whatnot.

I couldn't immediately remember the experience that led me to strongly believe it, but luckily the answer came to me in a dream. Turns out it's just personal stuff having to do with a past relationship that I cared a lot about. There are other concrete examples but they probably don't affect my decision calculus nearly as much in practice. (Fun fact: I learned many of my rationality skillz via a few years in high school dating a really depressed girl.)

And last, the rending pain of re-enactment Of all that you have done, and been; the shame Of motives late revealed, and the awareness Of things ill done and done to others' harm Which once you took for exercise of virtue. Then fools' approval stings, and honour stains. From wrong to wrong the exasperated spirit Proceeds, unless restored by that refining fire Where you must move in measure, like a dancer.

— T. S. Eliot, Little Gidding