I came across a very interesting discussion of “Consensus vs. Collaboration” which summarizes neatly why consensus isn’t always the best approach:

In consensus cultures people are rarely excited or supportive.  Mostly because they are very frustrated at how slow things move, how risk-averse the company is, how hard it is to make a decision, and especially how unimpressive the products are.

I saw quite a lot of that, and not only in Japan, so, yeah, that’s the way things are. And the bigger the company, the more pronounced this effect becomes.