For some time, auto experts have reported that objective quality differences have all but disappeared across most automotive brands. Indeed, the Detroit Three automakers have eliminated or substantially reduced large differences in defect rates after 90 days of ownership—no small achievement.

Yet, surveys continue to show that consumers consider quality an important factor in deciding which vehicle to purchase—and still give the nod to the Japanese and some other foreign automakers because of the power of past quality perceptions.

We are left with an intriguing question: Why has it taken Detroit more than a quarter of a century to close the gap? If we are skeptical about the latest claims, exploring the reasons for Detroit’s long road to quality parity may shed some light on the remaining challenges Detroit faces. It can’t afford to repeat its quality mistakes.

When the Detroit automakers did demonstrate bursts of dedication to quality improvement, these periods were followed by relapses and shifting priorities.

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