I describe management as arts, crafts and science. It is a practice that draws on arts, craft and science and there is a lot of craft - meaning experience - there is a certain amount of craft meaning insight, creativity and vision, and there is the use of science, technique or analysis.
Henry Mintzberg
What you get out of an M.B.A. programme, no matter how much experience, is functional tools and understanding in disciplines: you'll understand economics, you'll understand marketing, finance, accounting. That, M.B.A. programmes do very well.
Henry Mintzberg