Ongoing defects dropped by 60% from 2001 to 2011 and then dropped by another 20% from 2011 to 2021. The compounded reduction is 68%, a little more than two-thirds of the defects disappearing in 20 years.

JD Powers started its initial quality surveys in 1987 and its Vehicle Dependability surveys in 1990. The summary results are not easily found on the internet. The Consumer Reports defect rates are similarly restricted to paying customers.

https://www.yahoo.com/news/30-years-iqs-perspectives-history-222747086.html

In the 1980’s, Toyota and Honda offered significantly higher vehicle quality. Other manufacturers essentially “caught up” in the next 20 years. A snapshot from 1985 illustrates the gap that was closed by 2000-5, before the Vehicle Dependability improvements shown above.

The very disappointing 2022 results are inconsistent with the downward defect trend of the last 20 years, reflecting the pandemic production, supply chain sourcing and vehicle prep problems of the last 2 years.