I ended up doing this when I got my iPhone 6 because it was acting possessed. On all of my prior iPhones, I had restored from my previous phone’s backup. Ultimately, starting fresh fixed all sorts of weird little things as well as larger issues like TouchID: it had never worked for me on my iPhone 5S or my iPhone 6 until I did the fresh install on the iPhone 6. It’s more work to do the initial set-up, but I’ll be installing from scratch from now on.