Why are people getting induced?

As labor is approaching, I’ve seen so many posts about women having to be induced? Most women is getting induced at 38 or 39 weeks. Is that common for doctors to do? I’ve seen that inductions can increase a c-section? Can someone share how early they was induced or how late and the reason why? Did you have a vaginal birth or emergency c-sections? If offered an induction with no medical problems, could I deny it or prolong it? Any tips or feedback would be great :)