My hair is naturally VERY curly, so it took me close to an hour and half to completely straighten it back when I was in high school. That's not including the time it took to do my makeup. I used to a shower the night before, let it air dry, straighten it, got to sleep, wake up and straighten it again for about 10 minutes, then makeup time. I hated every minute of it, but I prefer straight hair over curly.
I went through a goth stage where I'd wear lots of dark eyeliner, and that lasted about a year. The last to years of high school I only wore concealer and mascara, but I still straightened my hair.
Now I could careless about my hair. I discovered hair gel. Wake up, shower, hair gel. lol I still don't like it, but the horses could careless. I still straighten my hair if I'm going out, but it's maybe once a week at most. My hair is so much healthier now because of it though.