Early on, I was comparing the game to something like Eclipse Phase, where the setting itself comes pre-baked with both actual and potential mysteries to explore in the fiction. Here, it feels like “explore your Mystery” is more like “you can do character advancement, just come up with some noir detective fiction to pair it with”. What do I mean by that?
Say that Tlaloc does more reading, and learns that the Aztec god Tlāloc had aspects of regeneration because of the rainy weather that helped the crops was based around Mount Tlaloc. There was child sacrifice, but also the idea of supporting and nourishing community. So I the player decide that the Mythos of Tlaloc wants to resolve this apparent conflict that evolving ethics has created for it: how are you making things better for your people when you ask them to murder their children? We come up with a new power tag like “tears call the rain”, letting Tlaloc know (or appear) wherever a child is crying or unhappy. Or we let him fix people up via rain or immersion in water - or heal himself when hurt. Or this might be big enough to develop into its own theme card.
There’s other gods that were identified as Tlaloc as well. Maybe he gets the ability to mingle with crowds better, or effortlessly disguise himself as someone else, facilitating more sneakiness. Water is protean and formless, so this power becomes a new power tag on the god-of-water card.
Similar evolutions might happen on his Logos cards. He becomes less a shifty two-bit crook, more of a community organizer - or becomes a larger player in the underground, a John Marcone figure who helps good people via bad methods.
So it sounds like Attention is there to sort of highlight which cards you’ve been paying most attention to, giving you time to think about all these advancement options.