Can I ask the rationale behind "eat crap one day, eat healthy other"? Why not just eat healthy (or better than "crap") both days and realize 2x the benefit? Thi

Can I ask the rationale behind "eat crap one day, eat healthy other"? Why not just eat healthy (or better than "crap") both days and realize 2x the benefit? This sounds like an excuse to rationalize poor eating habits. Also 4-9 hours is an incredibly wide range of sleep to prescribe.