Discrete production flow is normally adopted by firms who are manufacturing specialized products, example: custom built machines or where the volumes does not justify to opt for a repetitive kind of setup.

Also from finance perspective, when you want to trace the costs at order level & not by period.

What makes process manufacturing different from discrete?

Process manufacturing uses formulations or recipes. A discrete manufacturer uses Bills of Materials .A discrete manufacturer assembles along a routing, whereas a process manufacturer blends in a batch.

Therefore Discrete manufacturers – including make-to- stock, make-to-order, and assemble to order production facilities require sophisticated planning, scheduling and tracking capabilities to improve operations and profitability.

Whereas Process manufacturers with batch or continuous operations rely on sophisticated tracking and scheduling mechanisms to keep operations running at peak efficiency.

Discrete manufacturing is all about assembling things, and making things that are exact. The products are typically manufactured in individually defined lots, the sequence of work centers through production varying for each one of these.

Thus in discrete manufacturing, the product is made by sequential steps made in the same process or by the same craftsman. Discrete manufacturing based on the production orders and products change frequently from order to order.