More than half of the cars that presented for an NCT test in the first six months of this year failed.
According to stats from the Road Safety Authority (RSA), over 866,000 cars attended for an NCT between January and June this year.
Just over half of those failed with nearly 60,000 deemed too dangerous to drive out of the test centre.
Over 92% of the cars that were brought in for a re-test passed.
In 2018, the Skoda Yeti scored the highest pass rate in the country - with 81.3% of those brought in deemed safe for use on the road.
The Peugeot 208 supermini was the only other car model to achieve a pass rate over 80%.
Meanwhile, the Hyundai Trajet was the most likely to cause trouble at the test centre - with just a 20% pass rate.
These drivers had mixed views on whether the NCT was worthwhile.
"I remember the days when there were absolute wrecks on the road - it was dangerous," one said.
"I think people give out about it but it is necessary."
"Another labelled it a "total money racket," while a third said: "I would extend it for new cars for longer than three years because I think cars are built better. They last longer."
1.3 million vehicles were tested in 2018 - with just 49.2% passing on the first attempt.
With reporting from Kacey O'Riordan