The weight being carried by any type of ship must always be known and be taken into consideration when planning voyages. This is because:
- overweight ships may be unstable, harder to manoeuvre and may even sink
- extra weight will require more fuel which itself will cause more weight to be taken on and thus even more cost will be incurred. Extra fuel is also used in repositioning manoeuvres
- many regions have regulations governing the seaworthiness of ships. This includes stability and overweighting