Glad to find this thread.. I've had similar feelings when running projections of my own...
DW & I make $250k/yr gross. I'm 30 and she's 27. (This income is somewhat recent. We started around $32k and $45k, respectively. Found MMM about 2 yrs ago, had some debt, so current stash numbers aren't as high as they could be)
Current investments are low $200's. I figure at our current rate of stashing approx $135k/yr with decent returns we'll hit the FIRE target of $1.25m and a paid off house around age 35. Monthly spend is $3k/mo ex mortgage. [Yes, my numbers check out: 250k*75% = $187.5 after tax; 187.5 -16.5 mtg - 36k living = $135k savings.] SWR will be 3% on $1.25m to generate our $36k annually. Reaching the FIRE target in 5-6 yrs assumes no more increases in income between now & then. We just keep earning and stashing at current levels, and the returns are 7-9%.
But we'd be leaving cash cow jobs difficult to easily replace - especially if we fell out of the workforce for decades. I could get back here, maybe, but it would take years of grinding it out. Furthermore, we could realistically be making well above $250 in 5 yrs.
Now, to really heat up the convo, assume we went 5MY. Yes, five. Retirement is now at my age 40 instead of 35, but we would double our stash in those 5 yrs from 1.25 to 2.5M, assuming a 7% return and $135/yr additions. Now we really have zero worries. We can spend our $3k or more, educate kids, dip in for extra travel, etc. Our stache could be cut in half by the mkts & we wouldn't be at risk. And we still get to FIRE by 40.
It opens up a whole line of questioning about "enough", but the alternative would be to run low on funds in our 40's, 50's, 60's or later and have to go back to work or scurry to figure something out.
Hopefully between now & then I can see the light, stop being a wuss, find a way to generate more passive income. I dunno. These are just some thoughts that I've had on the subject. Get it while the gettin' is good then pull the plug worry-free. It's a sensitive subject & I have never posted this before for fear of major retribution from this crowd. But I'm all ears to hearing the alternatives. Although, respectfully, I'd be more open to feedback from other high-income, low expense posters who can actually relate to the opportunity cost at play. Easy for someone making lower income to judge high incomers for succumbing to OMY, but if presented with the real opportunity post FI to work for several additional yrs for literally millions - how would you respond? Think about that honestly. I wish I had the courage/character to say the money would no longer matter, but I'm not sure I've yet reached that stage of enlightment.