[jerf]

In addition to the other couple of replies that mention Japan, I would suggest, just start paying attention to this in the sense of deliberative practice, and you may find that your brain has been doing more editing on your social interactions than you may have realized. Sometimes the hardest things to see are the things we deal with all the time because our brains just read them as baseline. There's only a handful of cultures that are so blunt as to just say "no", bare and unadorned. Almost all cultures wrap a "no" in something to soften it. And I take a broad definition of "culture" here, including not just national, but company, family, other organizations, all sorts of cultures. You'll find it's quite a spectrum, and there's all sorts of inputs too, like positions in various hierarchies (perceived, formal, cultural, etc.).

You may also start doing this and realize that you personally have a mismatch with one of the cultures you participate in, which may even help resolve some small social problems you didn't even realize you were causing by bucking the particular culture's practices.

[retrac]

A similar effect: the imperative (giving orders). It is nearly as taboo in English, to just use the imperative, as it is in Japan. For example, if you have a dinner guest, you will ask "Would you like some more? Could you pass the salt?" It's always very indirect, put as a request that may be refused, or a suggestion. In other cultures, it may just be the bare imperative - "Eat more! Give me the salt." - and this is perfectly polite, contextually.

[dpassens]

Is "Would you like some more?" really a good example here? It's not really implying that the person asked ought to eat more, is it?

[grraaaaahhh]

It certainly can. For instance, when the speaker is my mother.

[spondylosaurus]

Maternal imperative mood: Any order or command phrased as a question, despite being non-optional.

Example:

"Do you want to turn on the fan?"

(Standard imperative equivalent: "Turn on the fan.")