You need that initial level of retirement income, indexed for the rest of your life.
I’m sure you can come up with a list of things that don’t fit the “set it and forget it” philosophy. Set the cruise control and forget it. Set the room temperature and forget it. Invest in a certain investment that has a particular risk associated with it and forget it. You need to make adjustments as the situation changes, as your needs and priorities change. Retirement income planning works like that.
Retirement isn’t one long vacation. It isn’t one period in your life. It represents the longest set of phases in your life. Each phase will have different needs for cash flow. You’ll need more money in your early, active years. You then settle down to a more normal retirement where expenses drop. Then late in life, poor health, the loss of your spouse or partner, losing your driving license and your attitude and behaviour will cause you to spend even less money. Yes, you may require money for long term care needs, but hopefully you planned for that before your retirement so that those needs aren’t coming out of your regular cash flow late in life. How much money you need and the most efficient way of getting it is something you should review every year, certainly as you experience life changes. Set up an investment and income stream that is flexible and adaptable to changing circumstances. Stress test the plans, strategies and components to make sure they continue to do the job they were designed to do. Life changes and your needs for income will change with them.