Berkson's paradox is one of the click-baity results you can obtain while doing conditional comparisons in your mind. For example, there is a common belief that Hollywood ruins good books. It appears that the better the underlying material the worse movie is. Sometimes this perception is attributed to a higher expectations for the movies based on the better source material, but there is an alternative explanation - the mental analysis itself ignoring substantial amount of the available data. This is refered to as Berkson's paradox.
In case for the movies, people often remember the instances when either source material was good or the movie was good. Namely, we tend to forger (ignore) the cases where both source and movie were bad. Because of that spurious negative correlation between the variables emerges.
Similarly there is a related belief that good looking people tend to be jerks. We experience this because when selecting our dates we tend to choose other people who are either good looking or nice. Namely, we ignore ones who are neither good looking nor nice.
More details on that in videos by ASAPScience and Numberphile.