Most retirement plans size the income bucket by guessing a portfolio percentage. The right way is to start with essential expenses, subtract guaranteed income, and let the gap define the bucket — not the other way around.

The 4% rule is a research finding asked to do a job it wasn’t designed for. It’s a useful sanity check, not a personal retirement plan. The better question isn’t what percentage you can withdraw — it’s how the necessary stuff gets paid for in a way that doesn’t ride on the market.