In American society, talking about money is a taboo. It is ok to talk about how much money someone else made when they sold their company, or how much money you would like to earn yearly if you got a raise, but in many different ways, talking about money is likely to trigger some embarrassment in the brain, and generate social discomfort. As one random example: no one dares suggest that bills should be paid according to wealth, for instance, instead people quietly assume that fair is each paying ~1/n, which of course completely fails utilitarian standards.
One more interesting thing people don't talk about, but would probably be useful to know, are money trigger action patterns. That would be a trigger action pattern that should trigger whenever you have more money than X, for varying Xs.
A trivial example is when should you stop caring about pennies, or quarters? When should you start taking cabs or Ubers everywhere? These are minor examples, but there are more interesting questions that would benefit from a money trigger action pattern.
An argument can be made for instance that one should invest in health insurance prior to cryonics, cryonics prior to painting a house and recommended charities before expensive soundsystems. But people never put numbers on those things.
When should you buy cryonics and life insurance for it? When you own $1,000? $10,000? $1,000,000? Yes of course those vary from person to person, currency to currency, environment, age group and family size. This is no reason to remain silent about them. Money is the unit of caring, but some people can care about many more things than others in virtue of having more money. Some things are worth caring about if and only if you have that many caring units to spare.
I'd like to see people talking about what one should care about after surpassing specific numeric thresholds of money, and that seems to be an extremely taboo topic. Seems that would be particularly revealing when someone who does not have a certain amount suggests a trigger action pattern and someone who does have that amount realizes that, indeed, they should purchase that thing. Some people would also calibrate better over whether they need more or less money, if they had thought about these thresholds beforehand.
Some suggested items for those who want to try numeric triggers: health insurance, cryonics, 10% donation to favorite cause, virtual assistant, personal assistant, car, house cleaner, masseuse, quitting your job, driver, boat, airplane, house, personal clinician, lawyer, body guard, etc...
...notice also that some of these are resource satisfiable, but some may not. It may always be more worth financing your anti-aging helper than your costume designer, so you'd hire the 10 millionth scientist to find out how to keep you young before considering hiring someone to design clothes specifically for you, perhaps because you don't like unique clothes. This is my feeling about boats, it feels like there are always other things that can be done with money that precede having a boat, though outside view is that a lot of people who own a lot of money buy boats.
I think it is partly about mixup, and partly because many people don't think clearly about their financial planning until forced to. If someone who makes 100k+ and spends most of it wants to retire in the same style they are used to living, they may well need 2-4M to do so comfortably and safely if retiring early. Social security is progressive, the max you can get as a single person is around 42,000/year. To get that, you must work for 35 years at a high income level and wait to draw your check until age 70. Then you still need to produce another 58,000 somehow from your own assets, which at current recommended withdrawal rates requires almost exactly 2M to do and maintain your wealth. Now, you could purchase an annuity for much less, but few people are comfortable dumping all their money into such vehicles. At current life income annuity rates, that would be a bit less than 1M$ to provide 58,000/year to a 70 yo. So you only need about 900K, but what if you want to retire at 65, or 60, or 55? Then you need to take less SS, or live off assets until age 70, or maybe you can't take it at all yet, and must live off assets alone. Whether you need 2M or 4M or more depends on when you retire, and how much risk of breaking your plan you are willing to take.
It's my job to model this for people. Most are surprised that they don't need 2 million or more, because their needs are more modest than above, and they don't plan to retire very early. That said it's different for everyone, and when younger people talk about stopping/reevaluating their career because they have enough money to retire, they usually mean in middle age not at normal retirement ages. At 40, unless your lifestyle is very frugal by the standards of people who are able to save 2-4M in that time frame (generally 100k+ earners), you probably do need that much to retire comfortably.
It also depends a lot on how you feel about your work. Most higher income earners have found a niche where they feel reasonably good about what they do (it's hard to create a lot of value when you feel like a cog or a moocher), and enjoy at least big parts of their jobs. In that case, why would you retire before you had plenty? OTOH, if you are burned out and it's a struggle to go to work every day, you might be willing to live on a lot less if you knew you could quit now, or soon.
Note: I know very few people who actually live like they are poor today in order to have great wealth tomorrow. Those who are very frugal while working, either are hugely committed to earning to give, or intend to retire or do something risky or different at a very young age, and don't ever intend to not live relatively frugally. Certainly they intend to either give away or enjoy the fruits of their industry long before a typical retirement age.
Two comments.
Inflation is very relevant. Especially when you are talking about annuities -- SS is more or less inflation-adjusted, if you invest your retirement money into equities it will inflation-adjust by itself, but if you buy an annuity that pays you $58K/year, that usually means $58K nominal dollars (inflation-adjusted annuities tend to be much more expensive).
For many people it is the case that they have paid off their mortgage by retirement age. Not having to pay a mortgage tends to noticeably reduce the living expenses.