“I'm out” is the phrase Dragons commonly say on Dragon's Den when they withdraw from a business deal.
The words signal that an investor is no longer willing to negotiate or make an offer. Because entrepreneurs usually pitch to several Dragons at once, one investor can leave the discussion while others continue asking questions or proposing different terms.
The phrase became one of the programme's most recognisable pieces of television language. It captures the finality of an investor's decision without requiring a long explanation, and it is often repeated by presenters, contestants and viewers when discussing a failed pitch.
It does not necessarily mean that every Dragon has rejected the entrepreneur. One Dragon saying “I'm out” only removes that particular investor; another may still offer funding, sometimes on terms very different from the original proposal.