Push Vs Pull

The idea that a company that practices pull supply chain methodologies will suddenly enjoy massive inventory savings and replenishment nirvana can be as flawed as the belief that the company that practises push supply chain methodologies will maximise sales and freshness in stores.

If you only use supply-side/ push methodology, your operations can be extremely efficient. Large amounts of standardized product can be positioned, but if the customer is not buying the product at the same rate, the real efficiency is lost.
In turn, if you shift to a demand-side/pull methodology, you reduce the production cycle and produce just enough to satisfy customer demand. When this occurs, you lose your manufacturing efficiencies, and you run the risk of not fulfilling unexpected customer demand.

Once we understand this paradox, we understand the 2 valid needs of the business (Efficiency and Effectiveness) but conflicting actions (Push Vs Pull) which we take to achieve them.
This is also the starting point for achieving a breakthrough.