I consider the blends present in a fabric as well as the pattern and color.

Cotton does not always hold up as well as a cotton/poly blend. If fabric stretches too much I might reconsider the application. I also look for tightness of weave especially if there are kids or pets. If I put a chenille on a sofa, I get the fabric backed which stabilizes and prolongs life of the fabric. Rayon can give a nice, shiny appearance, but that shine can wear off.

But construction and weave do not exist in a vacuum.

I consider where the item is going and how much wear it will get. A delicate fabric is often perfectly suitable in a formal living room or on a pillow.