How many actual users suspect that something is wrong with the input, even without URL obfuscation? OTOH, with a permanent XSS it is pretty much game over, even

How many actual users suspect that something is wrong with the input, even without URL obfuscation? OTOH, with a permanent XSS it is pretty much game over, even though I doubt that's the case. XSS can do a lot of damage if used properly.