Paper can be recycled into wood pulp until what happens?

The correct answer is that paper can be recycled into wood pulp until it becomes too weak. This weakness occurs due to the breakdown of the long cellulose fibers in paper through the recycling process. Each time paper is recycled, the fibers are broken down and become shorter, which limits their strength and durability. Eventually, after multiple recycling cycles, the fibers become too degraded to produce quality paper products.

While cost, moisture content, and color can impact the recycling process, they are not the fundamental reasons that determine the limit on how many times paper can be recycled into wood pulp. Weakness of the fibers due to repeated processing is the critical factor that ultimately dictates the recycling capacity of paper materials.