Multivariate statistics help the researcher to summarize data and reduce the number of variables necessary to describe it.
Scientists are curious.
They want to know what's there and why. They want to know what is behind things. And they want to do this in as parsimonious a fashion as possible. These are called dependence methods . They are not generally used in prediction, there is no p -value, and the researcher interprets the output of the analysis and determines the best model.