Been there, got the t-shirt.
I was with a previous company where we used phpBBB for a community forum. Guess what happened? It became a part-time job to manage the software and we still wasted a lot of time dealing with hacked sites (big pain to restore from backups) and removing (very) inappropriate content.
How much time have we had to spend maintaining Google Groups for the BigBlueButton project? Zero.
That means all that otherwise wasted time went into improving BigBlueButton for the community.
Regards,... Fred