Showering too much is bad for your skin. Washing your hair too much is bad for your hair.
~1000 years ago, you rarely bathed.
~500 years ago, you bathed once a year.
~50 years ago, you bathed once a week.
~25 years ago, you bathed several times a week.
~20 years ago, you bathed daily.
Now: "You didn't bathe in the last 5 minutes! Ewww! Gross. Not showering every 3 minutes is bad for you."
You have to cut it off at some point. I think every other day or every third day is about right for most people. Of course, if you sweat or get dirty, then wash regardless of the amount of time from your last shower.
If you bathe/wash your hair daily, you train your skin and scalp to constantly be oily since you have to keep replenishing what you washed away. But if you do it less often, you'll be far less oily as your skin and scalp learn that they don't need to produce much oil. From that point of view, you may be "dirtier" by doing it daily than by doing it every other day.