An electricity utility judges its repair wing by the share of consumer complaints closed within twenty-four hours, and reports that this share has risen from 61 in every hundred to 96 in every hundred. The utility concludes that consumers' supply failures are now being put right far more promptly than before. Which of the following, if true, most weakens the utility's conclusion?

Closure is a mark made by the lineman, not a supply restored, and once the wing is judged by closures the quickest way to a good figure is to close early. A third of the closures being reopened by the same consumer on the same failure shows the two coming apart: the wing's figure improves while the consumer's lights are still out. Eleven more linemen is a reason to expect genuine improvement and so tells for the utility. The several ways of lodging a complaint describe how the count is collected on the way in. And a tariff revision changes what consumers pay without changing how quickly a failure is repaired.