How long does your Dr wait to induce

Ni

So at my last appointment, my Dr told me to not expect to have my baby until 41 weeks. I was a little surprised because I thought most Dr's won't allow you to go over your due date. What's the longest your Dr wants to let you go before induction?? Just curious to see because so many women are saying their dr's are inducing at 39 for no medical reason.