問84
頻出度★★★
TCO (Total Cost of Ownership) の説明として, 最も適切なものはどれか。
平成22年度 春期 ITパスポート試験 問84
テクノロジ系システム構成要素 › システムの評価指標
This question's explanation and your answers so far.
解説
問 84
Incorrectア
“The total amount of operating and management costs incurred after the system is introduced” describes only the operating cost (running cost), one of the two parts of TCO, and leaves out the initial cost incurred at introduction. One part alone does not add up to the total cost of ownership, so it is an insufficient description of TCO and is wrong.
Incorrectイ
“The total amount of costs needed to deal with software and hardware failures that occur after the system is introduced” limits itself to failure response and maintenance costs, an even narrower part of the operating cost. TCO is a concept that includes, on top of failure-response costs, the initial purchase and development costs as well as the labor costs and electricity charges of normal operation, so this choice covers too narrow a range and is wrong.
- ウ
正解 The correct answer is ウ. TCO (Total Cost of Ownership) is the total amount of every cost spent while you own and keep using a system, and it consists of two main parts. One is the initial cost, which occurs only once when the system is introduced: the purchase price of hardware and software, development costs, installation and initial setup costs, training costs at rollout, and so on. The other is the operating cost (running cost), which keeps occurring after the system goes live: maintenance fees, electricity and communication charges, consumables, the labor costs of the operations staff, failure response, user training, and so on. Choice ウ reads “the total amount of the costs incurred when the system is introduced plus the operating and management costs incurred after introduction”, which is exactly the sum of these two, so it fits the definition of TCO best. The idea of TCO matters because a system that looks cheap when only its purchase price is compared can still turn out to be more expensive in lifetime cost once maintenance fees and labor costs in the operating stage add up; that is why whether to introduce a system, and the comparison of products, should be evaluated by TCO rather than by the initial cost.
Incorrectエ
“The total amount of costs incurred when the system is introduced” describes the initial cost, not TCO. If you insisted on judging TCO by the initial cost alone, you would overlook the maintenance fees and labor costs that arise after introduction and risk getting the comparison of lifetime cost wrong. That is precisely the reason the TCO indicator was brought in, so this choice takes the opposite view and is wrong.
ここがポイント
- TCO (Total Cost of Ownership) = initial cost (purchase, development, installation and other costs at introduction) + operating cost (maintenance fees, labor costs, electricity charges and so on after introduction). It is an indicator of the total amount spent while you own the system, and either part on its own does not make TCO.
- Do not decide whether to introduce a system, or compare products, on the purchase price (initial cost) alone; evaluate with TCO, which also covers the running costs after the system goes live. Even when the initial cost is low, high operating costs can make the total more expensive — that is the point this question is aiming at.
用語