One tries to make the best decision. Sometimes, however, people will successfully undermine the best decision if it does not accord with their beliefs. They may also contrive to get a second-best decision to work well. Further, if people are involved in the planning, they may have important information about the situation to contribute. Participative planning is often based on more complete information.
Participation also consumes time.
If this occurs, however, it is pointless to blame people for their resistance. That was inherent in the lack of participation. Note, too, that people do often tolerate occasional urgent decision. For example, if it is done only occasionally, for good reason, by someone they trust, it may provoke little or no resistance. I am not saying that participation will always lead to effective decision-making.