What does the captain need to monitor throughout the voyage?

The captain needs to continuously monitor weather conditions and navigational charts throughout the voyage because these elements are critical to ensuring the safety of the vessel and its crew. Weather conditions can change rapidly and directly impact navigation and operational safety. Accurate navigational charts provide the information necessary to safely guide the vessel along its intended route, allowing the captain to avoid hazards, allocate resources, and make informed decisions regarding course adjustments.

Monitoring the crew's well-being, the visual appearance of the vessel, and recreational activities onboard, while important, do not have the same direct impact on the immediate safety and navigation of the vessel. Crew well-being is essential for overall morale and effectiveness, and the vessel's maintenance is vital for long-term operability, but these factors are secondary to the immediate concerns posed by navigation and environmental conditions during a voyage.