A hot factor is a rear-view mirror. By the time a style has topped the table, you are buying it after the run, funded by selling whatever is about to turn. Chasing it is the recency trap in a quant costume.

Nobody forecasts which factor leads next. A rank correlation near zero is the whole story. What you can do is own all of them and let a rebalance sell the one that ran and buy the one that lagged.

The blend never wins a single year. It is never first and never last. Over a decade that shallower ride, held without flinching, beat the average factor you would have picked and then panicked out of.