Starting with Android 4.4, your device has checked to make sure everything is peachy keen when booting up. That thing has now developed even more in Android Nougat. Now, rather than just showing a message, it’s now blocking that buggy or corrupted software to run on your device.
So, Android Nougat has inbuilt system to prevent your device from running corrupted software. This has been introduced to prevent the attack of Malwares and Viruses. Google stated that this feature will allow users to use Android in a limited-use mode or it won’t start at all.
So, it’s another card in security metrics of Android.