I used to know a lady with a mullet...but then she cut it.
There was also a guy with a mohawk at my school. We used to call him "Mohawk Man".
I can't say I've ever had a bad haircut personally. I've used four barbers throughout my life. One died almost 11 years ago (he was my first barber). Another moved (I'd go to him sometimes if I couldn't get my first barber). There was another guy at the shop they were all at who I saw as well. I still see him sometimes, but most of the time I go to a good friend of my first barber. These guys know me well and have never given me a bad haircut.
I've seen a lot of people get bad haircuts/complain about their haircuts. Like this one time, a (female) friend of mine went from mid-back to chin length. She was so sad about the loss of her hair. I thought she looked cute with the new cut. Since then she has grown it to waist length.
Or, my favorite story. On a school trip in high school, a guy decided he wanted his head shaved by his friend. He had an electric shaving razor so he went ahead and started it. Well, one of the chaperones came into his hotel room and told him he had to get back to his (they weren't rooming together). So the guy getting the haircut had one half of his head shaved. The other half had hair on it. And it was perfectly divided down the middle. Sort of like the Two Face guy from Batman only it was hair. His parents almost killed him. When I saw him in school next his head was completely shaved.