Factoring Methods - Why is Grouping the 'best'?

I had a question about factoring. I know there are many methods and ways to factor, but what I wanted to know is why is grouping the de facto preferred way? For example, many educators say that they primarily teach factoring through grouping. Why don't they use other methods, such as X and Box? Is it because more people can understand as it is simpler?

 

Thank you,

Just Another Guest