The characters combine to form a vivid picture: “(to place one's) hands in (one's) sleeves and watch from the side.” This physical posture of having one's hands hidden and unavailable is a powerful metaphor for refusing to offer help.
`袖手旁观` is more than just a phrase; it's a moral judgment. In a culture that has traditionally valued collective responsibility and social harmony, the act of being an indifferent bystander is seen as deeply problematic. It violates the implicit social contract that people should help one another, especially those in their community. To a Western learner, this might seem similar to the “bystander effect,” a social-psychological phenomenon where individuals are less likely to offer help to a victim when other people are present. However, `袖手旁观` is less of a psychological observation and more of a direct ethical condemnation. It is the opposite of the highly praised virtue of 见义勇为 (jiàn yì yǒng wéi), which means “to do what is right in the face of injustice.” While an American might value “minding your own business” as a way of respecting others' autonomy, `袖手旁观` is almost never viewed positively. It implies that a situation clearly required intervention, but the person chose cowardice or selfishness instead. Public discourse in China often laments instances of `袖手旁观`, seeing it as a sign of eroding social morality.
This idiom is considered formal and literary. You'll frequently encounter it in news articles, formal speeches, and literature when discussing social issues, politics, or moral failings.
The connotation is always strongly negative and accusatory.