A container terminal charges for storage after a short free period, and the charges escalate quickly. The pricing exists to protect the yard, which is the terminal's real constraint.
The yard is the bottleneck
A terminal's capacity is not measured by how many boxes it can hold but by how quickly it can move them between ship, stack and gate.
Containers are stacked several high, and retrieving one from the bottom means moving everything above it first.
A full yard therefore slows every operation on the site, because each retrieval requires more shuffling, and the cranes spend their time rearranging rather than delivering.
Free time is a scheduling tool
Terminals allow a few days without charge so that importers can arrange customs clearance and transport.
After that, daily charges begin and typically rise in steps, which makes leaving a container in the yard progressively more expensive than moving it.
The intent is behavioural rather than financial. A terminal would generally rather have an empty slot than the storage income from a full one.
Delays are often not the importer's doing
A container can be held for customs examination, blocked by missing documentation, or stranded because no truck slot is available.
Charges usually continue during those holds, which produces the recurring complaint that a fee is levied for a delay the payer could not control.
Disputes over who bears such charges are common between importers, freight forwarders and terminals, and contracts increasingly address them explicitly.
Empty containers create the opposite problem
Once unpacked, an empty box has to return to the shipping line, and where a region imports far more than it exports, empties accumulate.
Storing empties consumes the same yard space as loaded ones while generating no cargo revenue, so lines reposition them on ships at their own cost.
Repositioning is one of the larger hidden costs in container shipping, and it explains why equipment can be scarce in one region while surplus sits in another.
Congestion feeds on itself
When a terminal fills, ships wait offshore, trucks queue at the gate and the yard has less room to work with each day.
Recovery is slow because the backlog has to be cleared through the same reduced capacity that created it.
Escalating storage charges are one of the few levers a terminal holds during such a period, which is why they rise sharply exactly when importers are least able to respond.