Next-day orders usually have a cut-off time to make sure there’s enough time to complete the delivery
Next-day delivery does have a higher priority among shipping companies than other standard deliveries. But there’s still a window of time that customers are given as a guide as to when to expect their parcel. To remain highly regarded and to avoid customer complaints, companies stick to their guidelines to make sure deliveries are made promptly where possible. Larger companies usually have a separate carrier for priority deliveries so that when these requests are higher in number, standard deliveries aren’t slowed.