The reason why we haven't developed those efficient attributes is because we come from a common ancestor whose traits we still have. Until humans mutate to become more efficient, then we shall continue to have our less efficient attributes. Also, evolution happens over the course of millions and millions of years. Humans have only been around for a few thousand years, but we are still evolving, just at a slow, slow pace. One example of evolutionary attributes we can see is pruny fingers, which allow us to better grip things.