If you did a reset that tries to save your personal data, that could be the issue. If the problem was something on the device you were trying to remove (due to it causing problems) by doing that kind of reset, the item casing the problems could have inhibited the reset. You can try starting the tablet in "Safe Mode" and see if it loads. While this is a restricted mode so not all things can be accessed, if it loads up, then you know there is something on the tablet you need to remove. Virus, malware, bad app, etc. If that is the case, you should back up your personal data to a google account or a computer, and then remove the problem item/items. If it still won't start up normally after that, try a "Hard Reset" to totally wipe the device...