Which production method involves no customization options for the customer?

The production method that involves no customization options for the customer is known as "Make to stock." In this approach, products are produced in anticipation of customer demand and are kept in inventory until sold. This method allows companies to benefit from economies of scale by producing large quantities of standardized goods, ultimately streamlining production processes and reducing costs. Since items are made in advance of customers placing orders, there is no customization available; products are sold as-is based on pre-existing inventory.

In contrast, assemble to order allows for some level of customization since the product is constructed from pre-manufactured components once a customer places an order. Job shop production is characterized by a high level of customization and is typically used for individual or small batch production tailored to specific customer requirements. A flow shop, while it focuses on efficiency and can produce a mass quantity of items, may not allow for customization depending on the context but still involves more configuration options than make to stock. Thus, make to stock is the only method in this list that operates solely on producing standard, non-customizable products.