Say you’re in a POW jail in Vietnam.
You’re a realistic optimist, so you whilst you know your stay will be extremely unpleasant, you think you’ll be released by Christmas.
The guy in the cell next door is an optimistic realist, so whilst he thinks he’ll survive his jail-time, he has no illusions of early release.
The first guy won’t make it. When Christmas comes and goes, and he’s still in jail, he’ll give up.
The other guy, the realistic optimist, will survive.
Same goes for entrepreneurs.
Better to think there’s no end date to the struggle, but that that everything will be ok in the end.