Maps that are excessively difficult to begin with, should not have any other autistic settings that push the difficulty even further. Maps that are difficult to begin with will already have a high loss rate, which easily drains team morale. Adding a layer of failnades round losses further kills that morale, increasing the possibility of that the map will eventually be set as "event only" or "never attempted again". Lose too much and people wont even play the map anymore out of negative reputation. For excessively difficult maps, good round are hard to come by such as having a high number of survivors midway though the map. If a failnade creates a loss within this sort of round, the event might as well be considered as over, shattering the hopes of players at the most positive moment. For easier maps people can handle the extra losses, but for harder ones, enough is enough for them. If a team is tryharding, no way in hell are they going to think an random loss by failnades is funny, and thus enabling this sort of thing on hard maps simply prioritizes one troublemaker over the vast majority of players. Its no different than trolling wall and killing off half the players in some cases.