In business, return on investment tells you what came back from the time and resources you put in. Fitness has an ROI too, but the return rarely arrives on your preferred schedule. People often quit because they expect visible results before their habits have had time to work.
Your early return may show up as better sleep, steadier energy or a stronger workout before it shows up in a mirror. Look at trends over weeks, not one weigh-in or one difficult day. Repeatedly starting over interrupts the very consistency that produces progress.
Give your plan a fair window, track what matters and adjust with patience. The book and companion manual help turn that idea into a practical approach you can follow.
A useful check-in looks at more than the scale: notice your training, energy, measurements and what you have actually done consistently. The return becomes easier to recognize when you know what you invested. Give the process a chance to show you a trend before deciding it has failed.