> It's usually part of a future worker's income. That is how they are underfunded. If the employee paid into a fund then these problems would happen less.

I was operating under the understanding that what you have so wisely suggested is exactly how pensions are generally structured, plus contributions from employers. Have I been misinformed?

I was also under the impression that these contributions are vulnerable to problems like assuming an incorrect long-term discount rate, life expectancy jumps, and more.