Decision Trees in Practice

They can also work because they are transparent.     But that transparency can also show when they are difficult to use operationally.   Which can be a good thing.

Why do Decision Trees Work?   in DSC
Posted by Amelia Matteson 

This article is from Win-Vector LLC: 

In this article we will discuss the machine learning method called “decision trees”, moving quickly over the usual “how decision trees work” and spending time on “why decision trees work.” We will write from a computational learning theory perspective, and hope this helps make both decision trees and computational learning theory more comprehensible. The goal of this article is to set up terminology so we can state in one or two sentences why decision trees tend to work well in practice.  .... "