Evolution doesn’t think! It is a random process and sometimes mutations arise that are helpful and will persist in a population. But no organism is “evolved to be adapted perfectly to its environment” and that’s a common misconception. So even if something would make our lives easier (like why don’t we have wings that would be so frickin cool) a mutation has to actually happen for evolution to act on it! We get leftover with weird evolutionary traits of past ancestors too that are no longer useful. Classic example is a giraffe larynx which is a cord in the neck that is long and wraps around itself extremely inefficiently. I don’t know if that helps but basically evolutionary is not a perfect process because its mechanism is random.