The issue is in the margins. Maybe a shift-change caused the surgical team to be different from normal, so people aren't as comfortable with each other. There

The issue is in the margins. Maybe a shift-change caused the surgical team to be different from normal, so people aren't as comfortable with each other. There's social/professional pressure to fit within a hierarchy, especially with new people. Maybe a few people lower on the totem pole think something might be off, but don't want to say anything lest they risk appearing to undermine the surgeon. So, at first it appears that a whole room of people would need to independently make the same mistake. But that's not so; only a few critical people need to make the mistake, and with enough ambiguity in the process (easily caused by anything happening 'out of the ordinary'), it won't be corrected some percentage of the time. Even seemingly trivial things. The FAA found this occurring in the cockpit, especially from the '3rd seat'. A pilot and first officer may be 'in the weeds' dealing with the immediate threat of a situation, whereas others have the benefit of distance to reflect on a situation and observe more clearly. They don't get tunnel vision, and are in a better place to diagnose a tricky problem. However, they may not feel empowered to speak up, or feel they don't have the information the pilots do. Aviation has, broadly, sought to correct this and encourage anyone to speak up. Recently, this happened during the flight before the Indonesia 737 crash where similar AoA/MCAS issues occurred, but a 3rd pilot helped to address the situation.