It depends on the arrangement and shipping service provider the company uses. If you place your order at 3PM, it may take two hours to pick your order. If they knock off at 5PM, you're boned, it'll get packed up the next day. Most small operations (that use FedEx, UPS or USPS) only have one outgoing pickup, and it's at the end of the day. Medium to large operations could have two or three.
This lack of understanding how goods processing and logistics work makes impatient Internet consumers really upset sometimes. Many treat the experience as if the world is a vending machine. Insert digital money, push button, get product. Any delay is seen as incompetence.
To add, being a former UPS employee, let's say this: the timeframe title you were suckered into buying means nothing. "Overnight" and "Next Day" are loose interpretations of how soon you think (or at what time of day you think) the package is being shipped. It's quite frequent to have boxes end up days late. Yes, there is a refund process involved, but it is usually from the shipper and not the receiver of the package. And good luck with almost any retailer following through with doing that for you.
Another little known fact: any package claiming to go by "air" "plane" or other such lofty (heh) title, unless it's more than 500 miles, probably goes by truck.
I have no idea why consumers pay for "quick shipping options." Here's a fun experiment, if you're loaded with spare income: place three orders with the same outfit that ships from the same location. Have one come standard. Have one come 2 - 3 day guarantee. Have another come overnight. See what happens. Most likely outcome, two out of three will be there in two days, the last one a day or two later.
Lack of patience and planning is profitable stuff.
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