Well, for starters because it takes at least 1 hour to eat breakfast, take a shower and get dressed + usually another half hour for the commute and some minor errands on the way.
Obviously that applies less if you work from home, since you can cut the shower and the commute.
I can wake up 7:50 and be in work, showered, by 8:10, including the 5-10 min commute. I think it varies a lot by person, just like productivity through the day!
>Sure, those hours are great for ingesting what has happened since the last cycle but not really for creating new value.
Why?