The simplest explanation: it's ready to be taken back to the dealer for the free warranty checkup. That's assuming you haven't already adjusted the rear derailleur to take up the cable slack that usually happens in the first hundred miles or so with a new bike.
I wouldn't skip the free checkup. The mechanic will check other stuff, too..
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You are always the same age inside.---Gertrude Stein
My aluminum bikes: Light, strong, cheap, and comfy.