It's not the same as in the US. In the US, consensus would be achieved through brainstorming, open debates, etc. and at the end maybe a vote, or maybe the lead

It's not the same as in the US. In the US, consensus would be achieved through brainstorming, open debates, etc. and at the end maybe a vote, or maybe the leader just says "let's try it my way, and if it doesn't work we'll do it your way." In a Japanese company, people in general do not speak openly in meetings, because they are afraid of disrupting group harmony. Ideas need to be circulated in a series of one-on-one discussions--this is called "newashi" (https://en.wikipedia.org/wiki/Nemawashi https://en.wikipedia.org/wiki/Nemawashi). This means that for a group of N people, it's N*(N-1)/2 private discussions that need to happen. And everyone needs to be in agreement and comfortable that the idea is "right", and that there is nothing the slightest bit off with it. Only after all these discussions have happened and everyone is fully bought-in, there is then a meeting to "rubber stamp" the idea.