Weaving was important for such obvious reasons as clothing, blankets, rugs and for selling and trading. In 1519, with the arrival of explorer Juan Cortez from Spain,also came extraordinary changes in weaving patterns, technique and equipment. Consequently, the conquering powerful European nation's style and the native cultures now blended their styles and their weaving reflecting this change. Inspiration for subject matter and patterns play an important role in the design. There are no rules in tapestry.
Western tapestries tend to portray religious themes.
But native Mexican works concentrate on geometric patterns. These are often precise due to their unchanging tradition and are pretty repetative. These designs are more than just random colors and threads coming together but weaves in mathematical patterns. Before one even starts weaving, say a blanket for example, one needs to create a sample from which to go by. This sample is planned out by counting the warps.