My financial advisor has pounded that in to me.
My investments with him are in several different places. Two annuities, that I'm collecting from. One Roth IRA, another IRA, and a trust account that I currently take money from. If that last actually gets depleted, I then have the other two IRAs to take from.
Oh, and to help you make some decisions, look at this: https://www.calcxml.com/do/how-long-will-my-money-last
I find it incredibly helpful. Their default assumption is that before tax earnings will be 8%. I always change that to 6%, even though in reality over the long term earnings are close to 10%. But I'd rather underestimate. Looking at that, even in recent market downturns, I'm okay.
I live modestly. I live alone, and even with recent inflation, my expenses are very low. This has a lot to do with being 73, retired, one child and no grandchildren. Yes, I do have a mortgage on my home, but the payment is very affordable.
I have one son, who is my heir. He is actually very well off financially thanks to gifts from grandparents and an inheritance from an uncle. I'm thinking of changing some of my beneficiaries on various accounts to others, nieces and nephews, who could honestly use the money more.
I always used to joke that my son would die a rich man, because his wants and needs are so very modest. That is still true. Which means, I need to think a lot about passing what I have on to others, besides him. I've already put my sister on an insurance policy, which is a start.