Rahul Mehta Gandhinagar LsCandidate

Everyday adter I get out of lift (elevator), I randomly press a button. What advantage does it have?
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eg I live on 3rd floor. When I get down from floor-3 to Ground, I press "1". And whenn I get up from ground floor to floor-3, I press "2" or "4".
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What advantage does it serve?
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