Buy Only What We Need, When We Need It
In purchasing goods and materials, we should not buy more than we need just because it appears more cost-effective to do so.
Buying extra leads to wasted money. Even if a quantity purchase would temporarily lower the unit cost, we risk the need for warehousing, or having obsolete items as specifications change. We may even end up with totally useless inventory.
A manufacturer should devote itself to creating profit from manufacturing. It is important to consider buying only what we need, when we need it.