People's sleep cycles are just different, even if it's not fashionable to acknowledge that. They differ with the person and they differ with the personal situation at the time. This notion that there is The One True Sleep Pattern and that everybody should adhere to it is not tenable in my opinion. It's a strategy that sells books on how to become "normal", nothing else.

I'm a night person, I viscerally hate mornings, and when I can I "oversleep" until 10 or even 11 in the morning. I go to bed when I'm tired, I usually sleep well and wake up rested in the morning. Sometimes I get tired during the day and when I can I respond to that by napping for a little while. In the absence of outside disruption, this works fine. I feel great and productive. On average I sleep 7-8 hours total, sometimes more, sometimes less. It's still possible to do a standard 7-to-5 workday, but after a while of doing that I simply become less productive and I start hating my day.

I've been told, directly and indirectly through "sleep experts" in the media, that my natural pattern is unhealthy and I must take steps to align myself with the same standardized day that is working so well for everybody else. Waking up feeling like you just got steamrolled, traffic jams, morning grumpiness, and being in the office before the boss arrives. Fuck that.