Is it normal to not brush your teeth?

I neglected brushing mine every day because I was always busy during the day and would collapse and fall asleep immediately at night. I didn't have a cavity for a while but then, all at once, I was hit with 7 cavities. One of them was so big that it wasn't worth saving so I had to have it pulled. This is not a good idea and I learned the hard way so I brush twice every day.