Scalability and specificity. 1) You can absolutely not be sure you would not later want to use something as generic as nav in a different context. Being heavy

Scalability and specificity. 1) You can absolutely not be sure you would not later want to use something as generic as nav in a different context. Being heavy handed with element selectors is a solid foot gun for scaling css. 2) Different selectors produce different specificity in css. To not write selectors that will later be overwritten, opting for class selectors is often a good idea.