Obviously. I mean that you can't protect the device from malicious power and usb outlets. And for non-malicious things the device should already have input prot

Obviously. I mean that you can't protect the device from malicious power and usb outlets. And for non-malicious things the device should already have input protection, otherwise it's unsafe to use if it doesn't when plugged in and unsafe leaving it plugged in unattended (you can die from electrocution or it can cause fire).