An inbound flight is late, and some passengers are trying to board a departing connection. Holding that outbound aircraft could save their trip, but it also delays the people already aboard and may cause new missed connections farther down the route.
The opening establishes the scheduled and actual arrival times, the outbound departure, and which travelers depend on it. One option departs on time and rebooks the missed group; another holds long enough to take them. The last comparison adds the following flight and alternative itineraries, making the downstream cost of holding visible. The question is not simply how many passengers are running to the gate. It is how long the missed passengers would wait for another route, and how a delay to the outbound flight would spread through later connections. The scenario is illustrative, but it captures why a local decision at one gate should be evaluated across a passenger network.
A port has a limited length of quay, and a ship must occupy one continuous stretch of it for the duration of service. Assigning an arriving vessel to the first apparently open place can block another vessel that needs a different length or arrival window.
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An electric train can return energy to the traction system while braking. Another train can use some of it if that train is accelerating at the same time and the electrical connection can carry the power. Without such a match, the opportunity may be lost even though the braking train still produces energy.
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Quay cranes are shared resources. Splitting them evenly between two ships may seem fair, yet keeping both ships in service longer can delay a third vessel that needs a berth. The time at which a ship leaves can matter more than how busy every crane appears at each instant.
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