iPhone recovery mode solved my problem, but why?
Today, my phone was stuck in a restart loop and it would never boot to the lock screen. I put my iPhone in Recovery mode, and selected in iTunes to update the phone's firmware, which didn't fix the problem and the phone was still in the endless boot loop. So, I put my iPhone in recovery mode AGAIN, and selected to do a restore in iTunes. The restore solved the problem. I would like to know how the restore fixed the boot problem, and what was the problem in the first place. To add more details, the endless boot loop started after I updated my iPhone to the latest version of iOS (it just kept on rebooting and rebooting after the update).
iPhone 6s Plus