The OBs I'm familiar with work in the office 2 days a week, seeing 35-40 patients each 8 hour day. The other days they are either in the hospital delivering babies/doing surgeries or in the classroom teaching medical students. Today's charting takes up far more time than actually seeing the patient.
The docs don't have much control over their schedules, and most hate when patients have to wait. Blame the front office/schedulers.
a good practice manager could do the one we had wonders. Her front desk people are oblivious. Most the problems were not her to be honest, it was all how her practice was managed (sole practiciioner practice, which i imagine can be a bit overwhelming)