Not paying attention properly is only human. Similarly, involuntary is agreeing or empathizing with the already known facts and beliefs. Yet such responses have a major impact in bigger life situations. The latter is effected by Selective Listening and the former by Confirmation Bias.
While we make decisions all through the day, be it small or big, it takes significant time, effort, and energy in taking wise decisions. Compared with individual decisions, team decisions make the effort multi-fold due to the involvement of multiple mindsets in the overall process. So, after spending so much effort, what if the conclusion is not even proper? What if you have to repeat the entire process?