Hindsight bias. It's very easy to look at the 3 winners over a long time horizon and say, "Look, they keep on going up and up." If this were a real trading strategy, then Momentum would sustain itself over a longer time, but the empirical academic evidence is that it's short term.

Over long time horizons, this tends to reverse itself. (Both companies and markets with unusually high PE ratios underperform low PEs over long time horizons) This is well accepted in finance. [0] [1]

[0] https://www.fidelity.com/learning-center/trading-investing/t...

[1] https://faculty.fuqua.duke.edu/~charvey/Teaching/IntesaBci_2...