Except emergency case, Japanese Shinkansen never delays.
The motto is being on time.
Likewise, Japanese society or community requires people to be on time in formal situations.
In the business scene, arriving at the office 10 minutes earlier is one of the social rules that every business persons try to protect.
Except accidents and emergency cases, people try to be on time just like trains in Japan.

While on the trains in Japan, everyone looks down at smart phones, but almost no one talks on the phone.
It's partly because it is supposed to be refrained because it can be very annoying to other passengers on the train.
Likewise, no one talks in the movie theatres.
And if you find ones talking on the phone on trains, many people cover their hand on their mouth so that they can talk quietly and avoid annoying behavior in public.
Is it weird? But it's pretty much common in Japan.

Almost none of Japanese people cut in line.
Try at popular ramen houses. Try at train stations. Try at amusement parks.
They definitely want to cut in line because they want to reach to what they want to get as fast as they can, but they know their own orders and always try to protect the unspoken rules.

It is prohibited to take photos on live concert because of copy right policies in Japan.
Even before the performance begins, concert staff members are overlooking for people who try to take pictures.
If you do, they warn you to try not to take any photos of the concert hall or live stage as well.

Couples don't make out in public.
They may hold their hands, may hug, may french kiss. Ok now they stop. No further than that.
In Japanese culture, making out in public is something very annoying or embarrassing.
Of course, you might have ever seen young Japanese couples making out in public sometimes.
Yes, sometimes you can see those people, but basically Japanese people think that's something very annoying.

Do you think these serious Japanese characteristics are annoying or too much?
But some of these are not spoken or regulated by the law, but they have their own unspoken rules that they try to regulate so that they will not annoy other people.
Sometimes, it may sound as if the Japanese lacks of freedom but most of them don't feel in that way.
Perhaps there might be some historical or traditional reasons hidden when they act like being too serious.
Japanese people love harmony which make things peaceful.