Onething

Onething is a term used to describe a philosophy or approach that emphasizes focusing attention on a single objective or task at a time. It is not a formal theory with a single origin; rather, it appears across productivity, design, and business discourse as a general principle behind prioritization and minimalism.

In productivity contexts, the concept is often associated with identifying a most important task (MIT) and scheduling uninterrupted time to pursue it. Proponents argue that concentrating effort on one task can improve outcomes, reduce distraction, and accelerate progress toward key goals. Critics warn that overemphasis on a single task may neglect interdependent work and may be impractical in settings that require flexibility.

In product development and design, the idea is used to justify a narrow scope or “one thing” focus—delivering a single core feature or experience before expanding. This approach can help avoid feature creep and clarify user value, but it may also limit iteration and responsiveness to changing requirements.

The phrase is popularized in modern culture by works such as The One Thing, a 2013 book by Gary Keller and Jay Papasan, which argues that extraordinary results come from focusing on the most important task. The concept has since entered business seminars, blogs, and branding as a general reminder to simplify priorities.

See also: deep work, prioritization, minimalism, single-tasking. The term onething is sometimes used as branding for apps or services that promote focused work, and its usage may vary across contexts.