> the goal of increasing your income/time ratio.

Not sure that's quite the right simplification of the appeal of passive income. Your time is fixed, the appeal of passive income for many is recovering more of your time. There's always more money you could make if you just get that next raise or promotion, so the most straightforward way to maximize your income/time is just to climb the corporate ladder and make more income.

An interesting issue with climbing the corporate ladder is that often your time spent actually increases. I've yet to find a role w/ seniority that is less than 40 hrs a week.

Some have even said that getting a promotion+raise can lead to less $ per hour because of a variety of factors such as more responsibility/time spent, increased requirement for dry-cleaning (suits or whatever)...

The cool thing about passive income is that there's a bit of a tax "trick" involved.

Because I'd rather have 5 years of $20k passive income than $100k in 1 year.

Well, I guess in SV it wouldn't matter, but in Amsterdam it does ;-)

You could increase your income to time ratio by getting a higher salary, no? Whereas passive income is about investing your income to make you money, which is agnostic of how much money you actually pull in due to salary.

out of curiosity do you apply this into expenditures too? ie spending time when it's expensive or spending money when its time intensive?

Classic examples could be learning to do automotive work to save money and hiring out cleaning services to save time. (please ignore the specifics, but understand the concept).