Traditionally risks for delays in getting into the berth were apportioned between the owner and the charterer in a way that all risk as to navigation, weather and alike were rested upon the owner and those as to congestion in the port or non-availability of the berth were on the charterer since it is they who determine the ports of loading and discharge, but some of these liabilities are usually transferred back to another party by way of exceptions.
In Margetson v Glynn  1 QB 337, per Lord Esher M.R. at p.340:
Therefore, the first thing which is always settled between a shipowner and a shipper of goods is the voyage. And, after the hundreds of years during which bills of lading have existed, we know the mode in which the voyage is generally described - viz., as from "the port in which the ship now lying," or at which the goods are to be shipped, to another port which is named…. The voyage described from Malaga to Liverpool, and, if there were nothing else in the bill of lading, the ship would bound to go from Malaga to Liverpool, according to the ordinary sea course for a steamer from the former port to the latter, and she would not be entitled to stop or to call at any other although it was in that course; she would be bound to go straight.