What's your tolerance for risk? At one end of the spectrum, you could liquidate all your assets and go to Vegas and put it all on black. At the other end of the spectrum, cash out every paycheck and buy gold and hide that under your mattress. The vast majority of startups don't make it.

Here are the possibilities (as I see them). a) You stay a a big tech company and it pans out. 20 years down the line, you're a multi-millionaire, you FIRE, life is good. b) You stay a a big tech company and it doesn't totally pan out for whatever reason. 20 years down the line, you've got the a decent retirement account for you and your spouse, and a college fund for your kids. You still have to work until standard retirement age. c) You join a startup. It hockey stick growths and you achieve multi-generational wealth. Mo Money, 'Mo Problems, though. d) You join a startup. It does okay. You get paid out enough for you to FIRE, but your spouse and kids aren't sitting pretty. e) You join a startup. It does okay. You get paid out enough for you to go on a nice vacation, but you're still going to be working until retirement. f) You join a startup. It does poorly. You paid AMT on options that turned out to be worthless. You're poor and destitute, living out of your car and eating cat food and totally burnt out.

A and C are awesome. B and D are okay E is... okay. F is terrible.

There's a lot of space between C and F. Life happens, so there are various other failure modes, but assuming they don't happen, know that A and B are possible. Assume C isn't going to happen. We can stick all sorts of numbers and give percentages, but at the end of the day, you've got to be able to live with yourself. The riskiest thing to do is to take no risks. Will you be on your deathbed, having chosen large tech company, surrounded by your kids and those kids regretting your life's choices even though it meant that you were able to provide a college education for your kids? If you're at large tech company and can't stand the sound of it sucking your soul out of your body, or think that it even makes that soul sucking sound in the first place, leave big tech co. If F happens and you're unable to dig yourself out of the pit because telling yourself "hey, at least I tried" isn't going to keep you warm at night, stay at big tech co.