It's a common question, and the most common two reasons are:
1) If your order is to a UK address, the courier such as Royal Mail or Hermes can only provide tracking information once the item reaches the UK. As a result of this, it may show "Shipping Label Created" or similar wording for up to 10 days until the item reaches a Royal Mail or Hermes facility. As soon as the item reaches the facility, the tracking will start updating almost daily until the item delivers. At this point as well you should receive a designated delivery date from the courier on our tracking page. We appreciate your patience on this matter and have staff checking packages daily so will notify you if there's something wrong with your shipment.
2) The parcel is currently in the process of clearing customs, which can take anywhere from 30 minutes to several days depending on the backlog of packages currently in customs.