No this isn't true. A cost is "sunk" as soon as the money (or time) has been spent. The fact that a cost is "sunk" shouldn't be confused with determining the

No this isn't true. A cost is "sunk" as soon as the money (or time) has been spent. The fact that a cost is "sunk" shouldn't be confused with determining the value of an expenditure. When you start throwing in "value" the whole concept gets confusing. Sunk costs _only_ mean that the fact that money has been spent on something should not affect future decisions. What you got out of spending that money should absolutely be considered in future spending.