If BGs weren't meant to start without enough players, it would have either been fixed in beta or put on the known issues list to be fixed in live.
But it seems like you don't understand how BG queueing works.
A BG starts when enough players hit the "queue" button, however not all of those players will hit the"accept" button to join the queue. Therefore there will be a few spots empty that would normally be filled with players that queued afterward. At this time, there aren't enough people to re-fill the queue. Thus, the game waits 120 seconds for more people and if not enough show up, the instance closes.
This has nothing to do with the queue starting too soon, it has everything to do with the lack of people hititng "accept."