I encourage you to test this hypothesis. I think you'll find it's incorrect. You can actually fail daily, in the ways you're most deathly afraid of (typically, looking foolish in front of others, facing a setback, or otherwise being knocked down a peg), and you won't die or worse (whatever "worse" is). People have tried this, for example instituting regimens of daily experiences of rejection, and it has only positive benefits.

Even a failed business or poor performance at a job won't kill you. These sound like worthier fears since they're more closely related to putting bread on the table, but typically the worst fears of corporate decision-makers are not that the company will execute poorly -- that usually happens anyway -- but that they will be blamed for it.

If we're going to talk about "failing" in general, I say fail as often as possible, even if this means the failures must be small.