Flight was supposed to take off at 8:10 a.m. Got up at "O dark thirty" to get to the airport by 6:30 only to have to wait until 10am for the flight to go. Had someone waiting for me at SFO-the wait was really long! No explanation from United. No apologies, no effort to put us on another flight. Really unhappy with United. Flying has become very uncomfortable, not only physically!