Why were the trenches constantly wet and cold World War 1?

The trenches of World War I were often wet and cold due to their shallow construction, which allowed rainwater to accumulate and create muddy conditions. The lack of proper drainage systems exacerbated this issue, leading to standing water and dampness. Additionally, soldiers faced harsh weather conditions, including cold temperatures and snow, further contributing to the uncomfortably wet and cold environment. These conditions not only made life in the trenches unbearable but also increased the risk of illness and disease among the troops.