I find that I often wake up at a decent time, but don't get out of bed immediately. This results in me falling asleep again for another hour. This process might repeat itself once or twice, resulting in anywhere from 1 to 3 hours of extra unnecessary sleep, when I could've been getting things done.
This doesn't happen if I need to wake up to be somewhere - it's only because I have a flexible schedule.
How can one break this habit?