overtime is only effective over very short sprints. This is because (as Sidney Chapman showed in 1909) daily productivity starts falling off in the second week, and declines rapidly with every successive week as burnout sets in. Without adequate rest, recreation, nutrition, and time off to just be, people get dull and stupid. They can't focus. They spend more time answering e-mail and goofing off than they do working. They make mistakes that they'd never make if they were rested; and fixing those mistakes takes longer because they're fried. Robinson writes that he’s seen overworked software teams descend into a negative-progress mode, where they are actually losing ground week over week because they're so mentally exhausted that they're making more errors than they can fix.
For every four Americans working a 50-hour week, every week, there's one American who should have a full-time job, but doesn't. Our rampant unemployment problem would vanish overnight if we simply worked the way we're supposed to by law.
We will not turn this situation around until we do what our 19th-century ancestors did: confront our bosses, present them with the data, and make them understand that what they are doing amounts to employee abuse — and that abuse is based on assumptions that are directly costing them untold potential profits
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