Most of us do not have enough assets to bring in income so that we can retire for life.
Nearly all of us have some assets that bring in income, but these are not enough to sustain us for long if we quit working.
A family may have some savings that brings in a few dollars per year.
At the current saving rate of less than a percent, even if you have $10,000 in the saving account, you will get less than $100 in interest. That is definitely not enough for retirement.
A family may have a room to rent to student or worker, and bring in a few hundred dollars per month. But that is not enough to keep us retire for life.
If they have an apartment to rent, and the apartment and their own residence are fully paid off, that is enough for retirement.
We have to build more or buy more assets when we are working, so that we have passive income for a long time.
The best thing about assets is that assets are transferable to the next generation. However, you have to do some tax planning to avoid the government getting the bulk of it in estate tax.