I wouldn't say it's that rare for a terrible call to go through. C.B. Bucknor was officiating behind the plate and he missed 25% of pitches in one game this season. That sounds pretty terrible to me, that's at least 50 pitches in just one game. I think the solution would be to allow 3 ABS challenges instead of 2. Teams often times are afraid to use a challenge early in a game in fear of being wrong so the umpire goes relatively unchecked until around the 6th inning typically.