Although there are days and weeks when you'll focus 100% on a single venture, over a period of at least months (not years), it's both healthier and a better long-term investment to spend some of your time and attention on future pebbles:

- 80% of your time: one core idea/company/venture (something in the middle of the bullseye)

-20% of your time and attention: the other future bets around ideas and tests...what's your next big thing?  This could be related to your main venture, or not...