The duration of shipment depends on the selected logistic provider, shipment method ans destination country. Check you country here.
And as per DHL/FedEx: sometimes there are delays because of human errors, technical issues, weather etc. Such problems cant be predicted. The stated standard delivery periods are average delivery periods, and are not contractual guarantied timings. If you do not receive the item 14 working days after expected arrival time, then please we will start a tracking process.