Every ship has an estimated schedule of days of route between one port and another, however there are certain routes that it is not possible to cover directly, and some transshipment is necessary in an intermediate port. It is usual for these transfers to generate a few days of delay because the arrival and transfer ships do not coincide as planned. Weather issues can also represent delays in travel days, especially on certain routes and certain seasons. Usually the delays arise due to the lack of spaces in the ships, which is known as container rolling, and means that by not having enough space for a certain exit, the container is waiting for a next one. This happens in times of high demand, with an emphasis on certain high-volume cargo ports. Every ship has an estimated schedule of days of route between one port and another, however there are certain routes that it is not possible to cover directly, and some transshipment is necessary in an intermediate port. It is usual for these transfers to generate a few days of delay because the arrival and transfer ships do not coincide as planned. Weather issues can also represent delays in travel days, especially on certain routes and certain seasons. Usually the delays arise due to the lack of spaces in the ships, which is known as container rolling, and means that by not having enough space for a certain exit, the container is waiting for a next one. This happens in times of high demand, with an emphasis on certain high-volume cargo ports.