I’ve worn my hair short for years and always washed it every 2 or 3 days. I don’t use a blow dryer very often, I never used a conditioner and my hair always looked healthy and shiny. Then, a couple weeks ago, we bought a hot tub. Now I have to wash my hair every night after I get out of the 'tub. My hair is dryish looking and feeling from all the washing. I bought some conditioner, and have been using it but it isn’t helping much. I’m going to have to do some research on conditioners and find something that works.
Due to very thick hair, I must wash it every day. If not, I go places and my “bed head” follows me everywhere I go.
If, for some strange reason I cannot, or did not wash my hair on day 1, I wear my trusty hat to cover the mess up. 
-Sam
My wife showers every day, but only washes her hair every other or every third day. She has beautiful fine blond hair that does not get oily. I have to wash my hair every day or it becomes an oily mess. The interesting thing is, if I work really hard and my hair gets drenched in sweat, when it dries, it is no longer oily. It feels like crap so I wash it, but it’s not oily.
I wash mine every two to three days…more often if it is really dusty or dirty. I have very long hair that reaches my waist in the rear, but is short on top. It is, for me, the best of both worlds. I don’t have a real problem with oily hair unless I wear my hat alot.
My hair isn’t waist length yet, but it’s getting there. Still, I wash it every day because I’m just such a greaseball that you can tell if I haven’t. I usually use a shampoo/conditioner combo like Pert Plus, but I’ve noticed that sometimes that leaves a greasy build-up that makes it look like I haven’t washed my hair, so I also have a bottle of Neutragena clarifying shampoo that I use about once a week or whenever I’m feeling greasy again.
I envy people who don’t have to wash their hair everyday.
I have to wash mine on a daily basis, otherwise it gets greasy and icky and I get zits along my hairline.
FWIW, I have short, but thick, red hair, and I don’t use glop to style it, nor do I use conditioner or a blow dryer.
OTOH, when I had long hair, (down past my shoulderblades) it was a pain to keep it clean cuz there was so much of it.
Robin
Shower caps make it simple to shower without washing your hair. You can also pin up your hair and take a bath.
I was told by several black co-workers that washing hair daily would cause it to break off or fall out. I assured them that it would not for me and they seemed skeptical. At the time my hair was only to my waist and I did wash it every weekday. All of them were very scrupulous about personal hygiene and appearance; I know it was not out of laziness (like me on weekends that I am on my own) that they didn’t shampoo daily, but rather out of concern for their hair.