First of all I personally have never seen a doctor perform a cesarean section delivery just because they want to leave the hospital. (thebirthguy.com)
In the case of an elective cesarean delivery, if the physician believes that cesarean delivery promotes the overall health and welfare of the woman and her fetus more than does vaginal birth, then he or she is ethically justified in performing a cesarean delivery. (attachmentparenting.org)
Failure to respond to fetal distress, and / or delay in performing a cesarean section when necessary (bwglaw.com)