The complexity of the guarantee was connected with the trade system on Java. The Netherlands Trading Society still had a quasi monopoly on the production of coffee, tea, sugar and indigo, and Dutch shipping lines could subscribe to transporting these for the lowest price. If this system was maintained, steamships would not get any cargo. Steamships had higher costs, but for the owner of the cargo a higher tariff was redeemed by lower capital cost, lower insurance cost and better quality. Therefore, the Netherlands Trading Society had to agree beforehand on paying for this advantage, instead of using (or being forced to use by law) her monopoly to drive down prices on steamships to the level of those for sailing ships.