You don’t “confirm” it. It’s an attempt to describe a system/outcome. It’s a model of a system, not the system itself and no model is perfect, because all models are our attempt to understand and describe things, and there is no such thing as perfect understanding.

However, it’s a highly accurate model, that explains things very well. So, either we will find that one day, we make a brand new, better model (this seems unlikely given the accuracy of the current model, but possible). Or, more likely, we continue to come to a better understanding of the system, and improve the model we use to describe it.