At the end of the day, KPIs, OKRs, MAUs, etc are all just numbers. What really matters is whether the value being exchanged is business worthy.
Like take an example about the Steam Deck recently by Valve. Gaben doesn't really care about these metrics right now because he's trying to validate a hypothesis that PC gaming can work as a handheld device (which has been tried for many years). Can it fail miserably? Maybe.
Or look at Mark Cuban's recent online affordable pharmacy. Mark obviously is showing he doesn't care about draining individual's bank accounts for life saving generic drugs, but validating if the big pharma industry is a bit corrupt and wants to slash the prices down. Can it fail miserably? Maybe.
Do you need business plans, balance sheets, or pitch decks to do this? Arguably not. You just need to know how driven the individuals/team is and whether there's a sense of product-market fit.