You also have to assume that you can maintain focus and efficiency for more than eight hours a day. I've worked fourteen hour days for weeks on end. I was young

You also have to assume that you can maintain focus and efficiency for more than eight hours a day. I've worked fourteen hour days for weeks on end. I was young, driven, and ignorant at the time. All I could smell was success. I felt like a hero waking up after a few hours of sleep each night and I'd quietly get to work. If anyone bothered to ask me how I did it, I'd just shrug and say, "someone's got to get this done." What a stupid asshole I was. The truth was I just felt like I was getting more done. Maybe on the first night or two of this I would. But after hour ten and eleven go by it started taking me longer to form sentences and get my ideas out. And it seemed that despite my best efforts writing unit tests and all that, my code would somehow still come out buggy. After a few weeks of this I wasn't being effective; I was just feeding the fire and making more work for myself. Now I find ways to get more done in a day before I just shrug and throw in more over time. This has lead me to become very disciplined in how I approach my day. Sometimes it feels a little routine, but I have more energy for my work and am ready to relax when I'm done. I show to the office 30-40 minutes early and get some code kata time in to warm up. Then I get a coffee, review team updates, and get down to hacking. When my editor is open I'm just coding. If it's not open, I'm at my whiteboard jotting down notes and making plans on how to solve the problem so that when my editor is open I'm just coding. Social interaction happens at specific points in the day and I keep it short and sweet. The afternoon is when I get the most work done. When five o'clock comes around I've usually gotten everything done that I wanted to do that day so I leave. Now that I'm a little older I see the young guys in the office doing what I used to. They throw themselves at the work. They work late for weeks at a time. They come to the stand ups all grizzled looking and swaying like an exhausted frond of seaweed. And sometimes they still manage to slip their stories for the sprint. You know what changed my mind? Death. We're all just getting older. There are no do-overs in life. Once your youth is gone it's gone for good. I don't have any kids myself yet so the center of my life is my career but that doesn't stop me from doing the things I want to do. I like to go camping, rock climbing, spending time with my wife and our friends. I like to spend lazy afternoons reading and occasionally stay up late writing. The worst thing I can imagine is wishing you had enjoyed your time on this earth more when you had the chance.