Low players. Always low players. For PVP or vs AI

What I don't understand is, if a game mode suffers from low player count, how can one player trying to play the game sit and wait for 15 minutes to be put into a match against AI? And have an error come up after saying that they couldn't find a game for them?
Half the problem is there ISN'T ANY GOD DAMN GAMES TO JOIN.

Why, after 5 min of waiting. is a new game not made, with all bot teammates and enemies, to get things rolling? Let people join in, Get second and third matches going.
Pretty sure people have dailies they'd like to get done, but matchmaking mechanics are prohibiting it.

edit: I've seen new games generated for me for Dominion and Breach AI, where new players joined 20-60 seconds into a match. I've also joined games that are over half way into completion (assuming a player left and I filled in the spot, but when i join a game that is 980-100, do players really drop matches to prevent quest completions? Seems kind of mundane. I've been disconnected after the end of a match and not made any progress so that doesn't seem like a viable explanation.)