Scrum guide mentions that working at a sustainable pace improves focus and consistency. It's mentioned just once and the guide doesn't go deeper into it, but it's still an extremely important guideline to keep in mind.
I was reminded by this when I went really hard for a week.
I had lots of important and exciting things lined up, many high stakes meetings, travelling and to top it off, a whole weekend being at Agile Coach Camp Finland 2022. The camp was both absolutely amazing and also the last nail in my coffin, as it feels like I'm still recovering even though it's soon been two weeks.
The classic book The Mythical Man-Month mentioned that using overtime actually slows you down. If you are in a hurry, you can loan effective working time from the future but you always have to pay it back afterwards and there's a pretty brutal interest too. If on the first week you have to crunch and you do two weeks worth of work, the next two weeks you probably can manage only 0,4 weeks worth of work per week. So the total for the three weeks ends up being less than what you would have managed if you had worked at a sustainable pace.
This is an oversimplification and usually the costs of overtime are much more subtle (but equally real and important!). In this particular personal case it was very obvious that I had overdone it a bit though. It was interesting to see how many things I couldn't manage after a week like that. Working out, handling all the promises I've made during the busy week, even keeping up pretty established habits was all extremely hard.
At least I had the option to focus on getting better. My sprint goal for that week was to "Prioritise rest". Doing Scrum was again very helpful as I could use it to stay focused and committed to resting instead of trying to be as productive as usually because of some lingering protestant ethic. Scrum made it transparent that this week I can not expect to handle every possible task but will have to pick and choose the most highly important and urgent ones and postpone the others. This again helped me to let some customers know that they might have to wait for next steps a bit longer than usually.
It all worked out and I felt much less guilty than I have usually felt for being tired and prioritising resting and taking it easy.
Which was nice, but even nicer would be to work at a sustainable pace always. It's not fun being completely spent even when you see it coming and have decided to pay the price this time. Sometimes situations require some crunching and sometimes it makes sense to squeeze everything out of a week even if it means you have to rest for a couple of weeks afterwards. Using Scrum at least gives you a way to try to make those choices consciously and maybe next time you realise it might not make so much sense after all...