You can keep a low hit-rate and focus on giant returns by playing the lottery, but fortunes are built on compound interest and diversified portfolios.
Reducing the number of failures does not mean getting rid of the big winners. It could mean focusing on large existing industries over speculative, pie-in-the-sky trends.
Think about ZenPayroll (disclaimer: early employee there, biased.) Product-focused payroll is not sexy, but the impact is massive and a tremendous business opportunity. We're now building software for local governments. Not sexy, huge market, huge impact on humans, clear path to single, double, and home-run.
My biggest frustration with looking for founding teams chasing these speculative bets is the sheer waste of human talent. I don't want to see another all-star team waste their time on bitcoin and food-delivery.
There are real, serious problems with the same upside but whose "failure" scenario may be a $25m business.