Dividends made sense 40 years ago as a relatively simple rule of thumb, but after all the work done by John Bogle with index investing, and academics with Monte Carlo sims and the 4% rule, dividend investing just isn’t the simplest, cleanest way to invest or receive passive income anymore. It’s actually significantly more risky compared to index investing, because dividend companies are a much smaller share of the total global economy compared to the broader indices.

That income is considered residual income because as long as the apartment is rented and the rent is collected, the income is earned without additional effort. The effort came when the property was purchased and a tenant was found. Each month after that, the money automatically is paid without buying the apartment again or finding the same tenant each month.
Inspired by you, I started a tax/personal finance a month ago. I figured if it works out, it will create a good side income for me. If not, at least I can use the blog to build my brand as a tax lawyer. Other than that, my current investment portfolio is heavily focused on index funds because of its historical performance and tax & cost efficiency. Right now my dividends income every year is about $14,000. I also have a good amount of unrealized capital gains every year from my investment, though I don’t count the capital gains as my passive income as they are paper gains, at least for now.
Managerial accounting defines residual income in a corporate setting as the amount of leftover operating profit after all costs of capital used to generate the revenues have been paid. It is also considered the company's net operating income or the amount of profit that exceed its required rate of return. Residual income is normally used to assess the performance of a capital investment, team, department or business unit.