“Each obviously invested considerable sums building assets that were intended to serve them a long time, and the abandonments would have a similar effect to someone just reaching into the treasury and thowing money to the wind. Wouldn’t it?”
The above is what my Engineering Economy textbook referred to as “the sunken cost fallacy.”
Here’s an example that will illustrate what they meant by that term:
Suppose a company (or even an individual) has an older vehicle; it needs new tires and the transmission is making ominous sounds. Should it be repaired or replaced with a new vehicle? To answer that question we’ll do an economy study to determine which alternative costs less.
For the old vehicle repair cost are R1, its estimated life is L1, yearly operating cost is O1, yearly maintenance cost is M1, and salvage value when retired is S1.
For the new vehicle first cost is FC2, estimated life is L2, salvage value is S2, maintenance costs are M2 (which should be less than M1 since the new vehicle is in much better condition), operating costs are O2 (less since new vehicle gets 30 MPG vs. 20 MPG for old vehicle), and there’s an overhaul cost OV2 halfway through the new vehicle’s service life.
We want to determine the annual cost of the two alternatives; to do so the one-time charges such as first cost are converted into an equivalent annual cost using the appropriate formulas and interest rate (i*). The i* used may be the cost of borrowed money, or the company’s desired profit margin, or may be set higher yet, especially if there are many projects to be considered but very limited money available for them.
Once everything is converted to annual charges they are added together to give a total annual cost for each alternative, and a meaningful comparison can be made.
In our vehicle example let’s assume that Alternative 2 (buy new vehicle) has a lower annual cost which indicates that’s the preferred alternative. “Wait a minute,”