Jobs to be done
The lens that says people hire products to make progress in a circumstance - 'a milkshake hired for a boring commute' - so the competition is whatever else could do the job, including doing nothing. Sharpest for innovation and messaging; its caveat is that buyers of a category often share the same broad jobs.
Where it's used
Used in product development, messaging and competitor mapping. Good for finding rivals you never listed, because they do the same job in a different category.
Example
What the shake was hired for
The morning milkshakeClayton Christensen's team found that a fast-food chain sold many milkshakes before 9am, to lone commuters. The shake was competing with bananas and bagels for a long, dull drive: it fits one hand, lasts the trip, and keeps you full till lunch. A better flavour would not help, but a thicker shake would.
