Reference reading
Complacency
Taking past performance, fluent output or a safety reputation as assurance that further attention is unnecessary.
The first hundred runs went well. The inspection hatch has become decorative.
Unwarranted satisfaction with one's adequacy that weakens needed attention or improvement.
Proportionate confidence and reasonable reliance differ.
How it takes hold
The system has performed well for months. Its reputation now supplies an answer before the new case is examined. Confidence in previous work gradually becomes a reason to stop doing the work that made confidence reasonable.
Complacency is unwarranted satisfaction with adequacy that weakens needed attention or improvement. It can concern personal skill, an institution's reputation or a familiar tool. The habit does not require claiming perfection; it can live comfortably inside the phrase good enough when the relevant question has stopped being asked.
Changed circumstances may go unnoticed. Those reporting a difficulty must first overcome the reassuring history of cases unlike their own, and an opportunity for a small correction can become a larger problem.
Finding the distinction
Illustrative situation: a trusted system is assigned a new kind of case.
Too complacent: its reputation is treated as the evaluation.
Fitting: relevant differences receive a proportionate check.
Overcorrection: past success is treated as suspicious and no reliance is permitted.
Arrogance inflates importance or judgment and discounts correction. Complacency centers assumed adequacy, which can be quiet and modest in manner. Negligence identifies disregarded care; complacency is one distinct orientation that can weaken it.
Proportionate confidence is useful. Successful experience can support justified reliance, and constant unease is no measure of responsibility.
Counterfeit of Discernment: A reputation for reliability replaces attention to a changed use. Genuine Discernment asks whether the original grounds still apply.
A response that restores something
Confidence remains informative when its scope is clear: this process has worked under these conditions for these purposes. New uses deserve attention to what has changed.
A review can focus on relevant signals rather than merely repeat a reassuring checklist. A complaint, changed audience or new source of data may matter more than another clean run of familiar examples.
Improvement need not disown earlier success. A mature account can preserve the achievement while accepting that continued adequacy requires renewed care.
Other perspectives
perhaps further experiments are necessary to bring it to perfection
Charles Babbage · On the Economy of Machinery and Manufactures
Babbage's observation leaves a working technique open to improvement; prior promise does not finish evaluation.
unless every window-pane was perfectly clean
Booker T. Washington · Up from Slavery
Washington recalls Davidson participating in preparation herself; the context illustrates maintained attention, not a universal standard of perfection.
Read and compare
Which changed condition could make yesterday's assurance insufficient?
Humility · Attentiveness · Diligence
These are constructive virtue readings, not a list of automatic opposites. This reference article does not score character or assign a vice to its reader.