DaveMatthew
Bring in Peter
That’s what xGA , xGF, GSAX, and others stats all due now, try to predict, and yes nothing is guaranteed, I think we all know that.
Those stats don't try to predict the future. They try to analyze the past.
xGF is how many goals you should have scored in the games that already happened. Not how many goals you should score in future games.
People look at those metrics and then use them to try and predict the future.