Politeness
No one wants to be considered 'impolite'. The problem is that what is considered polite in one culture can sometimes be quite rude in another.
In English we often 'soften' a request through our use of language - "If you don't mind..." or "If it isn't too much trouble...". However, in other languages these sorts of structures don't exist and so people can appear rude or overly direct.
In some cultures politeness is shown by simply not saying anything ... deciding not to give your opinion to avoid offending the other person. In other cultures this might be considered impolite.
This short video helps to understand the challenges of trying to be polite around the world.