Slowness and inefficiency of port operations is an obstacle to increased foreign trade, particularly for developing countries. Many ports have failed to keep pace with the rate of expansion of the country's overseas and coastal trade. The initial result is port congestion, with significant increases in trading costs. Disruption of trade follows, and eventually trade is forced to adapt to the limited port capacity with a permanent detrimental effect on the national economy. The appearance of a scarcity of tonnage can result from port congestions and slow turnround of ships at ports. This in turn can lead to excessive shipbuilding and an overtonnage situations as port management improves its traffic handling.