I guess that Many foreigners who visited Japan felt everything in Japan was very clean.
Because keeping cleanliness is one of our cultures. I think that cleaning is important for us practically and spiritually.
Especially cleaning whole house conducted in the end of year is very important.
As I mentioned some days ago, we tend to draw a clear line between the new year and the old year, so we don’t want to carry over the incidents which happened this year. they include dust and stains. To welcome the new year’s day, we want to feel refreshed.
There is an English word “spring-clean” or “spring cleaning”, I think cleaning whole house in the end of year in Japan is close to this for western people.