I brush twice a day probably 98% of the time -it is rare that I do not brush at night as wake up feeling awful -very occasionally I will also forget in the morning if I get carried away with other things!
I try to brush and use mouthwash twice every day, but sometimes I miss. Often if the kids are asleep I pee before I brush my teeth...and of course the noise of the toilet wakes one of them or I just decide that teeth brushing is too noisy and not worth the risk of waking a toddler!
Guess I am the odd one out here, and I'm somewhat embaressed to admitt it. I brush at least once a day, twice if I'm motivated and three times if I'm paranoid. If my mouth feels clean, that's good enough for me. (Baby in image is not my son, LOL).
Sometimes my morning teeth cleaning is closer to lunch time if I get busy and distracted during my second cup of tea. I always brush my teeth before I go out and always before I go to bed, so it would be rare not to brush twice a day.