Ask Culture and Guess Culture
One source of interpersonal misunderstanding and conflict is the difference between Ask Culture and Guess Culture.
In Ask Culture, you're allowed to ask for just about anything, and you also have to accept that your request might be denied. In Guess Culture, you can only ask for something that you're confident the person you're asking will be willing to provide. When people from Ask Culture and Guess Culture interact with each other, it's easy for both sides to the see the other as rude.
Although the difference is framed in terms of making requests, I think it has more to do with whether or not you're allowed to deny a request.In Ask Culture, you're allowed to deny a request for any reason. But in Guess Culture, denying a request is considered impolite, unless you've got a really good reason. If someone makes a request that you just don't want to accept, you're forced to either do the thing even though you don't want to, or be impolite by refusing. Which is where the implicit rules about what you can request come from, because you don't want to put someone else in that situation, or for someone else to put you in that situation.
Furthermore, it's not a simple dichotomy. What counts as a really good reason to deny a request will vary from culture to culture, and some cultures will have more or fewer than others.
A related topic is making offers. In some cultures (at least, so I've read) you're expected to turn down an offer. The first offer is only made to be polite. If they really want you to have it, they'll offer it again. It's considered rude to accept the first offer.
This feels to me like a continuation of Guess Culture. Not only are you not allowed to deny a request, you're required to preempt the request by making the offer first. But because you still might not want to actually fulfill the offer, the recipient is expected to turn it down.
Of the cultures I described, I think Ask Culture is the best. And I say that even though I'm more naturally inclined to Guess Culture. But, explicit communication is less prone to misunderstanding than implicit communication. Guessing what another person wants or is willing to do is generally less reliable than asking them.
While I do think we should strive to Ask more, we should also recognize that different people have different expectations and different preferences, and we should strive to be more accepting of those differences.