I have a theory behind this rule. I borrowed it from Tony Schwartz. The theory is after about 90 minutes the average human starts to lose focus and higher-level cognitive functions drift. Most artists, developers, writers - you cats - are above average, so maybe you get two hours at the outside. So after about two hours the extra-ordinary human loses the ability to differentiate between minute details, which is what these silly, frustrating, "why-can't-I-figure-this-blasting-thing-out" problems are all about.
The solutions to silly software problems that make developers like me crazy end up being things like:
- I included a source file instead of a header file.
- The index was 0 instead of 1.
- The name of a variable was misspelled - "tacoTrock" instead of "tacoTruck".
- I accidentally overloaded a method name as a variable.
But these practices are not enough; even if you write perfect code with perfect style, you're gonna hit a wall.
When you hit the wall, walk away. Over the past month or so I've tried to step away for 10-20 minutes when I hit the wall. When I return to work I've found the answer in less than 15 minutes. Every. Single. Time. And when I don't step away? I waste upwards of an hour and don't get the answer.
Every. Single. Time.
Maybe I'm insane or just far below average, but I doubt it. Rather, I think we all have to manage our energy very carefully. Skeptical? Just try it - run your own experiment.
If you're a type-A overachiever you will probably feel bad about not working during those 10-20 minutes. I know I still struggle with these feelings. So try saying,
"I am running an experiment. Good science makes for good products, so practicing this good science for two weeks is a good idea. At the end of two weeks I will evaluate my progress. In the meantime, I can't argue with how nice it is to walk up to the coffee shop in the sun..."If you wonder why I'm at Verite most days between 2:30 and 4:30 it's because A) the Red Sox don't start playing until 4:15PST most days and B) I generally need that walk-to-the-coffee-shop break 2 hours after lunch!
Want to know more about managing your energy? I wrote about it in Shipping Greatness, and you can also read Tony Schwartz's book.