Why is it much easier to open a bottle the second time?

Opening a bottle becomes easier the second time because of a phenomenon called “break-in” or “wear-in.” The initial opening of a bottle often creates some friction or resistance between the cap and the bottle’s neck. However, after the first opening, the threads or seal on the bottle cap have been slightly adjusted or worn, reducing the friction. As a result, subsequent openings require less force and feel easier.

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