Hey, if it’s failure you want to be assured of, I’ll introduce you to my Mother-in-Law. According to her, whatever you do will fail. (She only ever did one thing right, and I married that success.)
In real life, almost everything you do is a failure — until you get it right. You certainly can learn from failure, but I’d rather learn from success — and then duplicate it.
If you want to look for a successful startup, look at combining the recent resurgence in spouse swapping with house swapping. A holiday with spice. You couldn't lose, sex and accommodation. Send the kids off to the in-laws for a week or two and let it all hang loose.
They have apps and organisations for almost everything nowadays. Someone should start a “Rent a Butler” service. Go over well when you are holding a party.
Of course, I won’t play. No one is getting their hands on my wife. She’s as good as they get.