Ask what makes it real. A factor needs an economic reason it should pay you, a risk you are taking or a behaviour you are exploiting, not just a line that happened to fit the past. No story, no factor.

Demand a higher bar. When hundreds of patterns are fished from the same history, the usual significance test means almost nothing. The real survivors clear a much tougher bar and keep working on data they were never built on.

The boring few beat the exciting many. Size, value, momentum, quality, low volatility have held up across decades and across markets. Most of the 452 were noise wearing a backtest.