The job of an entertainment rigger is to safely suspend objects (scenery, lights, sound equipment, platforms, and even performers) at very specific locations above the ground. The type, size and location of the structural members from which these objects must be suspended vary greatly from venue to venue. Additionally, the size, weight, and location of each object varies from object to object. To ensure that each object is safely suspended at the proper location, math is essential. Sometimes this math is very simple, and sometimes it can be complex. One reason catastrophic failures occur is because the load placed on a structural member or a piece of hardware exceeds the breaking strength of the structural member or piece of hardware. While a structural engineer must determine the strength of the structural members, and the manufacturers determine the strength of the hardware, the rigger is responsible for knowing the forces that will be exerted on each rigging point and piece of hardware. Because the forces placed on each rigging point and piece of hardware are determined not only by the weight of the object (its static load) but also HOW the rigging is done, entertainment riggers must be able to calculate these loads/forces. There are plenty of entertainment riggers who do not know how to do much math - but these are the people doing exactly what they are told to do, and not the ones figuring out what to do and doing the telling. If you want to be a top-notch rigger, you have to know math.