Why do they call IE's the "jack of all traits"?

I think the term is "Jack of all trades" and it is used with many engineering disciplines, especially if the engineering is a project engineer. Industrial engineers along with mechanical engineers have a very wide area of influenced and if they have the chance will learn about many aspects of design in their carrier, they and can solve many problems, thus becoming a "Jack of all trades". The full saying is...."Jack of all trades,.master of none" which is not fair since they master the whole process or project. If you work as a project engineer, you will have to become familiar with many aspects of project development from client meetings, developing solutions, picking equipment, managing installations and starting up to managing schedules and budgets. Smaller project have one engineer so they need to be able to aster all the phases. Good engineers are great problem solvers and people come to them for solutions in many areas. I like engineers that can apply their problem solving expertice in many areas.

Specialty engineers (auto, aerospace, computer, mining, environmental, solar... for example) on the other hand have a narrower area of expertise, but will delve much deeper on solutions, technologies and future direction of the discipline. These engineers secure higher degree levels and usually stay in one industry. Engineering company may have a few specialty engineers to manage very complicated issues in a certain area.

After earning a degree in industrial engineering, you can typically begin your career in almost any field. The great thing about IE is that everyone who is looking to improve processes and save money requires some sort of industrial engineer. This can come in the form of process engineers, supply chain engineers, quality engineers, manufacturing engineers, continuous improvement engineers, and so on.

Most industries require IEs, and often times they’ll require that you perform many tasks. You’ll have to understand the business and finance side of an industry as well as the operational side. You’ll have to use the knowledge of both sides to bridge the gap and make substantive improvements. It wouldn’t be unusual to act as a project manager,

covering IT and Procurement as well as balancing the finances and implementing process improvements throughout.

Simply put, IEs can do it all!