I have a sort of pride that comes from not feeling pinched even though I live much more frugally than others. Perhaps that is a great place to be after I FIRE, but during my accumulation phase I should feel a little pinched.
That's entirely down to mindset, and that's a good thing. It means you've completely let go of the need to have new consumer goods and services for whatever reason.
That's why I always agree with MMM that reducing expenses is better than trying to earn more. Reducing expenses also builds the mindset of being comfortable (physically, mentally and emotionally) with less stuff. That will also help you when you retire.
Continually earning more and more is great, and it may mean that you retire super early and/or with a ridiculously large stash. However, a seemingly ridiculously large stash will disappear very fast if you're retiring with the mindset of needing to spend loads, always having to eat out at the best places, do fancy things, have the latest stuff and go abroad all the time for vacations.
Being able to cope with less helps both in working toward early retirement, and also with being retired early, late or whenever.
If you're able to find genuine pleasure, relaxation and fulfilment in things that cost little or no money, then you're basically a black belt mustachian. That's what I reckon anyway.