PPAP specifies the general requirements for the approval of production parts, including production and bulk materials. The purpose of PPAP is to determine whether the supplier correctly understands all the requirements of the customer's engineering design records and specifications, and whether its production process has the potential to meet the customer's requirements according to the specified production rhythm in the actual production process.

After the product passes PPAP, it can be mass-produced, which is carried out according to a certain output and time period. That is, from what time to what time in the first stage, how much output is planned and what is the linear speed of production (for example, 5 pieces per second). With the stability of equipment and materials quality and the improvement of workers' operation speed, they will enter the next stage, from what time to what time, what is the planned output, and what is the linear speed of production (for example, 8 pieces per second) until the expected linear speed and output are reached. The improvement of production line speed and output is also called climbing. The production plan of the whole climbing stage is the mass production climbing plan.