Some leagues don’t like to take points away from their players for mistakes like interceptions and fumbles. I think it’s a necessary evil.
If your quarterback records two touchdown passes but also tosses four interceptions, why is that a good day?
Turnovers kill teams in the NFL, and logically the same should be true for fantasy teams.
Subtract points for interceptions, fumbles lost, and I’d even argue taking away a point for a missed extra point.