I missed 6 time in a row with 81% hit chance. Nothing is impossible but here the probability is less than 10^-3.
This is a 1 in ~20.000 chance, not that hugely far off Tim Cain's Fallout example. It's long odds, but given the number of rolls and players, it should occur with some frequency.
The problem is that it happens consistently to the same player and across the player base. As for the fact that if you have a 3:1 critical miss/critical success ratio is indicative the RNG doesn't work properly.
