The threat of lawsuits is one reason, and doing C-section can be equated to a form of defensive medicine:

“They’re never faulted for doing a c-section,” said Faith Frieden, chief of obstetrics and gynecology at Englewood Hospital and Medical Center in New Jersey. “It’s never the wrong decision to do a c-section. No one’s ever going to say to them, ‘why were you so quick to do the cesarean section?’

“Usually what happens is, if anything goes wrong, then they’re questioned later on, ‘wouldn’t it have been better if you did the cesarean section a little sooner?’ ‘Why didn’t you do the c-section?’ ‘Wouldn’t that have been the easiest way to deliver this baby “” the less traumatic way to deliver this baby?'” Frieden explained.