The 4-Hour Workweek by Tim Ferriss promises that you can reduce your working hours to four per week while maintaining or increasing your income. The book was published in 2007 and has influenced an entire generation of people who now work eighty hours a week trying to set up a business that will eventually let them work four hours a week, theoretically, someday, maybe.
Create a "muse" — a low-maintenance online business that generates passive income. Outsource everything to virtual assistants. Automate your income streams. Then travel the world while your business runs itself. This sounds amazing and is approximately as achievable as time travel for most people.
Setting up the muse requires research, product development, website building, marketing, customer service systems, and the management of virtual assistants who need to be trained, supervised, and occasionally replaced. This is not four hours of work. This is a full-time job, plus your existing full-time job, which you need to keep until the muse generates enough income to replace your salary, which for most people is never.
Ferriss's book is useful if you extract the principles: question assumptions about how work must be done, eliminate unnecessary tasks, batch similar activities, and learn to say no. These are good ideas. The four-hour promise is marketing. The lifestyle design concept is compelling. The execution is realistic only for a specific subset of people with specific skills, risk tolerance, and financial cushions. For the rest of us, the book is aspirational fiction — enjoyable to read, impossible to implement, and slightly depressing when you compare the promise to your reality.