If you have a limited amount of time to dedicate towards activities and you want to maximize the reward you get, the strategy is obvious. You want to put as much of that time as possible into things that have these huge rewards. And so this is a mathematical model of opportunity cost because when you would instead spend an hour trying to get some of these small reward activities like looking for the funny thing on Twitter or say happy birthday to the old roommate,. That's time that you could have been getting a much higher reward. The steel type away from those things is something we should be very cautious about.