In five preregistered studies, we assess people’s tendency to believe “kids these days” are deficient relative to those of previous generations. Across three traits, American adults ( N =3,458; M age = 33-51 years) believe today’s youth are in decline; however, these perceptions are associated with people’s standing on those traits. Authoritarian people especially think youth are less respectful of their elders, intelligent people especially think youth are less intelligent, well-read people especially think youth enjoy reading less. These beliefs are not predicted by irrelevant traits. Two mechanisms contribute to humanity’s perennial tendency to denigrate kids: (1) a person-specific tendency to notice the limitations of others where one excels, (ii) a memory bias projecting one’s current qualities onto the youth of the past. When observing current children, we compare our biased memory to the present and a decline appears. This may explain why the kids these days effect has been happening for millennia.