An industry is a systematic economic activity. It produces physical products or services. Jobs have to be planned. Time schedules for these jobs, or for tasks within an assignment, are necessary. Without the schedules there would be chaos. This is easy to understand. The role of operations planning and scheduling is, therefore, clear. Since the time ‘craft’ became an ‘industry’ businessmen have understood the role of planning/scheduling production/operations. In fact, one may argue that those nations/peoples that consciously cared for time industrialized faster. Those nations that believed in a lax or relaxed concept of time may have had crafts but these industrialized rather slowly. Thus, ‘time’ has been associated with industry.
However, the focus on time in the early half of the twentieth century-the century of worldwide industrialization-had been about bringing order into the otherwise chaos. It was regarding making one’s own life a little easier. There was this demand function for the products that needed to be addressed to. In a job-shop environment, the already given promises had to be met. This involved some planning and a lot of short-term decisions or fire fighting. Production had to be planned and then the deviations (which were normal) had to be controlled. Time was something that a market demanded or an individual customer asked for. Time was a constraint.
For a long time it was all simple and straight-jacketed. Production/operations had to have a long range plan, a plan of activities for say 5 to 10 years. This plan had to be brought down to the manageable yearly, and then quarterly or monthly plans. This would help in broad allocation of facilities. This was the intermediate range plan or aggregate plan. Then, based on these plans, the weekly/daily work schedules had to be made as to which particular machine and which person will work on which particular job. This planning was and is good. It is necessary to plan future work so that the demand and available capacity can be matched. Work has to be organized in terms of the long-term future (mostly forecasted) requirements on the production or operations facility, the intermediate term real loads on it and the actual production in the short-term. This line of thinking is valid even today. However, one needs to realize that this is only one dimension of time. It is a view that treats time as a constraint posed by the market. It is a quantitative view.
Somewhere around three decades ago, management thinkers started realizing that the role of production could be much more than just producing a product. If the product was produced and delivered at the time when the customers needed it, it gave much satisfaction to the customer. Timeliness was realized as a much desired quality. This timeliness had to be from the customer’s view point. It was not enough if a firm delivered on promised time. As the promised time could be a compromise between ‘when the customer really wants the item’ and the capability of the firm’s production system as to ‘when it could make the item’, if a firm could deliver actually at the time the customer needs it, it would amount to a delightful experience for the customer. Toyota Motor Company realized that promising the customer that her car will be available three months later and then delivering the car to her exactly after three months is one aspect of punctuality. However, if a customer could pick up a car any day she walks in to their showroom, it would amount to a whole new experience for the customer. Toyota Production System came into existence to provide this kind of service to customer. It was a service provided Just-in-Time. Therefore time became a vital element of service quality.