以TDD做為外包商績效指標之研究-以某記憶體製造公司為例

Abstract

個案公司之外包商管理是由外包商管理委員會來執行日常事務及進行每月績效評估工作，其外包商績效評估方法是由委員會各部門之績效評估指標以特定比例加權而成的。然而隨著產品線複雜度增加及市場需求變化快，現行外包商績效評估指標已不能有效地引導外包商及時調整生產優先順序以滿足客戶的需求並做出符合發包公司最大的利益的決策。本研究發現其外包商績效評估有以下幾點問題：第一，現行績效評估指標沒有考慮到時間與金額的效應，不能有效引導外包商以發包公司最大利益為考量之決策。第二，現行績效指標是多樣且多重階層結構，績效評估過程需經多個部門之計算整合，通常績效指標之收集與統計費時冗長，無法快速統計出外包商績效並提供做為生產決策之參考。第三，現行績效指標中未明確定義考核規則之比例過高，個人主觀判斷會對績效評估的結果有很大的影響，無法公平判斷外包商間績效之差異。過去有許多文獻提出外包商績效評估指標與評估方法，然而這些指標及方法仍是由多種績效指標組成之組合，也與個案公司一樣會遭遇相同的問題。限制理論(Theory of Constraints, TOC)強調以整體觀與產出觀來看待組織之整體表現，並提供了一種評估組織績效的新指標：產出-元-天(Throughput-Dollar-Day, TDD)，其定義是：因交期延誤而無法出貨的訂單產出損失金額，TDD低表示出對貨且交期準，此指標是以產出獲利影響為依歸，激勵所有人以公司最大利益為考量，再者TDD計算式簡單明確，應該是一套合適且可行的外包商績效評估指標。

In the case , the subcontractors management and subcontractors’ monthly performance ranking are handled by subcontractor management committee of the company. The final performance score comes out from every department of the committee which is weighting in specific proportion. Due to product list become more complex and market demand change more frequent ,The current subcontractor performance index can not lead subcontractor making the decision which toward greatest profit for consigning company and can not fulfill customer’s requirement by adjusting priority of producing. We found some problems of the current subcontractor performance index as following .First ,the effects of time and amount of money did not be considered into current subcontractor’s performance index, it will not lead the subcontractor’s decision toward the consigning company’s greatest benefit. Second, the current performance index is multiple stratum's .It take a long time to figure out the final performance score .So it can not be a reference for real time production decision making .Last ,almost half score of the index need personal judgment .It is not fair ,hard to tell the performance among the subcontractors .Many papers proposed out the subcontractor’s performance indexes and assessing methods in the past, but these indexes and methods are all the combinations of various kinds of sub-indexes. They will cause same problems as case company. Theory of Constraints(TOC) regards a organization’s performance as a whole throughput , and it offer a index for organization performance assessment. That is Throughput-Dollar-Day(TDD),which is defined as the loss amount of throughput due to delay. Low TDD means that company deliver the right goods at the right time .In addition ,TDD align to the company’s greatest profit and encourage all people act toward this target. Besides, TDD’s formula is simple and clear , it make TDD to be a better and more suitable index of subcontractor’s performance assessment.