Explanation

Just-in-time (JIT) purchasing is a systems approach for developing and operating the purchasing function. JIT purchasing along with the total quality management in many industries has been suc-cessful in reducing inventory and increasing the overall effectiveness of purchasing function and hence the productivity of manufacturing.

The just-in-time objectives of eliminating waste can be summarised in the 'five zeros: zero defects, zero set-up times, zero inventories, zero handling and zero lead times.

The correct answer should be 'In JIT purchasing, raw materials (or goods) are purchased so that products are delivered just as needed for production or sales' because it expresses that upstream activity (purchasing) only occurs as the downstream activity (production or sales) triggers.