What is a common reason for a diver to opt for a dry suit instead of a wetsuit?

Choosing a dry suit over a wetsuit for diving primarily revolves around the enhanced thermal protection it offers. A dry suit creates a barrier that not only prevents water from entering but also allows for the use of insulating undergarments. This combination significantly increases a diver's thermal insulation, keeping them warm even in extremely cold water conditions. Unlike wetsuits, which rely on a thin layer of water being warmed by the body, dry suits maintain a complete seal that isolates the diver from the cold environment, making them suitable for colder waters where thermal protection is critical for safety and comfort.

The other options, while relevant to diving, don't match the primary reasons for selecting a dry suit. Mobility can vary depending on the material and design of both wetsuits and dry suits. Cost factors are often higher for dry suits due to their construction and technology. Lastly, while many divers find dry suits manageable, the initial adaptation period can involve learning specific donning and doffing techniques, making them less convenient than some might expect, especially for beginners.