There are enough people queued up but it doesn't match into a game, just ticks over to the next 3 minute round. I've just got into a match now, was doing that for like 30 mins
Infinite matchmaking
My understanding is that if there is not a "good enough" match you will not get matched (like if a 0 and a 2000 are in the pool).
I am not saying I agree with this, just sharing that that's the way it is.
IMO I'd rather play a "bad" match than play lobby sim for 30 minutes, but I am just one vote. Maybe there should be a "force match" timer, like if you are unmatched for two cycles, you are guaranteed to match on the third (provided there is at least one other player). Or more flexibility on what's a "good" match every missed cycle.
The other day, I joined the queue, started watching something on youtube, forgot I'd joined the queue, went to make dinner, ate dinner, came back to my PC and got matched in a game, all in all it was over an hour 
@pearl12 True. I wouldn't mind getting slaughtered by a pro if only to peep their strats.