When combined, 多管闲事 (duō guǎn xián shì) literally translates to “to manage many idle/unrelated matters.” The logic is clear: you are spending your time and energy managing things that are not your responsibility—other people's “idle affairs.” This immediately frames the action as unnecessary and intrusive.
Understanding 多管闲事 is a window into Chinese social etiquette and the concept of personal boundaries. In many Western cultures, particularly in the US, there's a value placed on “speaking up” or being a “concerned citizen.” Voicing an opinion on a community issue or giving a friend unsolicited life advice might be seen as proactive or caring. In Chinese culture, however, there is often a stronger emphasis on social harmony and not causing others to “lose face” (丢面子, diū miànzi). Openly interfering in someone else's affairs, even with good intentions, can imply that they are incapable of handling their own problems. This can cause embarrassment and disrupt the social harmony. Therefore, 多管闲事 is a powerful social corrective. Accusing someone of it is a clear signal that they have crossed a boundary. This boundary isn't necessarily about privacy in the Western sense, but about respecting social roles and spheres of influence. A parent getting involved in their adult child's life is usually seen as 关心 (guānxīn - concern), but a colleague trying to manage your personal work schedule without being asked is definitely 多管闲事. The line can be subtle and is defined by relationships and context.
多管闲事 is used frequently in daily conversation. Its connotation is almost universally negative.