Why is stretching watercolor paper important?

Stretching watercolor paper is a crucial process primarily because it helps to prevent warping when water is applied to the surface. Watercolor paper is designed to absorb moisture, and as it becomes wet, it can expand and then contract as it dries, which may cause the paper to buckle or warp. By stretching the paper beforehand, artists can secure it to a backing board, allowing it to remain flat and stable during the painting process.

This practice is particularly significant for artists using heavy washes or large amounts of water, as the risk of warping increases with the amount of moisture applied. Proper stretching ensures that the paper maintains its original surface characteristics, resulting in more controlled and predictable painting outcomes. Other options do not address the primary functional benefit of stretching; enhancing color saturation and increasing thickness are irrelevant to the stretching process, while flexibility is more about the characteristics of the paper itself rather than the technique employed.