I get that, but how much more? And what is the reason for the error? That is, are the models bad, or the scenarios? The models don't control the inputs, aft

I get that, but how much more? And what is the reason for the error? That is, are the models bad, or the scenarios? The models don't control the inputs, after all. If it is just the inputs are different from actuals, that is very different from the outputs are wrong