Another alternate explanation:

When you're bored, you entertain yourself by generating arbitrary complex behavior to no particular purpose. Sometimes, while you're doing this, other people notice something you did and give you resources for it.

When this happens, you re-categorize the particular activity that got the resources, from "arbitrary complex behavior I generated for no particular purpose" to "things that get resources from people".

In other words, from "mapping out the space of possible activities" to "generating value in an economy".

Or, from "explore" to "exploit".

Or, from "play" to "work".

Once an activity is successfully classed as "work" — that is, something that gets other people to give you resources — you don't need to do it unless you want more resources. If you don't want more resources right now, you can safely spend time exploring other possible activities. But if you get hungry/poor/etc., you can go back to the best "work" you've found so far, to get resources you need.

(Similarly, some things may not get you resources from others, but may get you attention, affection, status, etc. — which probably gets a distinct classification such as "social activity".)