Design for manufacturing, also referred to as design for manufacturability or DFM, is the process of incorporating restrictions that may be present from intended manufacturing methods into the product/part models during the initial design stages. This helps reduce the need for rework when a product is ready to be manufactured.
An example of applying DFM is when designing a part of which the intent is to manufacture using injection molding. Design restrictions such as undercuts, parting lines, and mold cavity filling need to be considered prior to a mold being built. If these are not addressed prior to mold building, the potential is high for issues like parts stuck in the mold cavity, poor part quality, and very expensive tooling.