What is the purpose of using a pilot hole when driving screws?

Using a pilot hole when driving screws primarily serves to reduce the risk of splitting the wood. When screws are driven into timber, especially near the edges or in hard woods, the wood fibers can be forced apart. This splitting can compromise the structural integrity of the wood and lead to undesirable results in carpentry projects. By pre-drilling a pilot hole, you create a channel for the screw that allows it to enter the wood more easily and without exerting excessive pressure on the surrounding wood fibers. This not only helps preserve the quality of the wood but also ensures that the screw is driven more accurately and securely, enhancing the durability of the joint being formed.