The 4% rule also assumes that you blindly spend exactly the same amount (+ inflation) every single year with absolutely no reduction in spending under any circumstances whatsoever.
That doesn't exactly sound like reality to me.
Based on what I read here, I expect that the vast, overwhelming majority of posters here will not only not run out of money, but will end up with huge gains over their retirements.
I see more plans with sub-4% WR, plus a hefty cash store in case of recession, plus fat in the budget, plus paid off housing, than I see lean plans with no ability to modify spending and no option to generate income.
I've seen A LOT of posts from post-FIRE people talking about how they almost never spend their entire yearly allotment, effectively lowering their average WR even more.
I'm not criticizing, DH and I will likely end up functionally somewhere near a 1.5-2% WR at the end of all of this unless we learn to start spending a lot more. Lol
It's not intentional, we just like our jobs and don't spend much.
My point is that you can do all of the math you want, but the inputs are fundamentally inaccurate and vague because it's all just guessing roughly what you will spend in the future.
The math stops being even remotely accurate unless you literally think that you will spend the exact predicted amount every year.
That presumption is nonsense, which means all outputs are nonsense.
I'm all for assessing risk, but pretending like there's some actual accuracy in specific withdrawal rates and simulations is an illusion when the inputs are fundamentally imaginary.
Simulations help a lot with gauging the relative magnitudes of different risks, but they simply cannot apply to a specific situation and outcome, and they completely ignore the risk factors/mitigations that are already baked into the input data.
Nothing is guaranteed.
Save approximately 25X what you expect to need yearly in retirement, save more if you want to be more conservative, save less if you want to be less conservative.
That's pretty much as reliably detailed as you can get in predicting your success.