If those things are multiplicative rather than additive, then improving one of them by 10% does make your whole life 10% better.
Obviously real life is more complicated than either a simple additive model or a simple multiplicative model. But I’d expect there to be things that operate multiplicatively. E.g., suppose you have a vitamin deficiency that means your energy levels are perpetually low; that might mean that you’re doing literally everything in your life 10% worse than if that problem were solved.
(Obvious conclusion if the above is anything like right: it’s worth putting some effort into figuring out which problems you have affect everything else so that making them 10% better makes everything 10% better, and which are independent of everything else so that making them 10% better makes everything 0.01% better.)
If those things are multiplicative rather than additive, then improving one of them by 10% does make your whole life 10% better.
Obviously real life is more complicated than either a simple additive model or a simple multiplicative model. But I’d expect there to be things that operate multiplicatively. E.g., suppose you have a vitamin deficiency that means your energy levels are perpetually low; that might mean that you’re doing literally everything in your life 10% worse than if that problem were solved.
(Obvious conclusion if the above is anything like right: it’s worth putting some effort into figuring out which problems you have affect everything else so that making them 10% better makes everything 10% better, and which are independent of everything else so that making them 10% better makes everything 0.01% better.)