Flawed classification systems persist because sunk costs and absent alternatives outweigh their failure.

Evidence

Basically, the DSM recognizes that its basic methodological framework of mutually exclusive disorders does not work. My suspicion is that the DSM sticks with it because it lacks any clear alternative and because of the massive sunk costs in the existing typology. — Gary Goertz, Social Science Concepts and Measurement, 1254

Categorization

• SEED: Essay angle: ‘sunk costs of bad categories’ — how institutions cling to classification schemes they know are broken, from DSM to regime typologies.