This idiom advises against disrupting a stable, successful, or well-functioning situation, warning that such actions could cause chaos or loss. It suggests preserving the status quo, likened to an apple cart that, if tipped, scatters its contents. The phrase is used in social, business, or family contexts to advocate caution and respect for established systems, often with a conservative or protective tone. It can imply resistance to change but also a practical concern for avoiding unnecessary trouble.

The phrase likely originated in 18th-century England, tied to market life where apple carts were common and upsetting one caused literal disruption. An early use appears in a 1788 *London Chronicle* article: ‘He upset the apple cart with his rash proposal.’ The idiom gained traction in the 19th century, reflecting agrarian and commercial concerns, as seen in Charles Dickens’ *Bleak House* (1853). Its metaphorical use grew in American English during the 19th century, particularly in political contexts, with Mark Twain using it to describe risky reforms. The phrase’s vivid imagery and relevance to stability ensured its spread across English-speaking cultures, especially in business and diplomacy.