Nearly one in three Bay of Plenty people sitting their restricted licence test this year didn't have the chance to complete it.
NZTA figures show Bay of Plenty's termination rate for restricted licences was 32 per cent between January and September.
The figure refers to tests not completed due to an immediate failure error or the accumulation of several critical failure errors.
Immediate failure errors include collisions, failure to give way, excessive speed and failing to stop. Critical errors include going too slowly or too fast and failing to look or signal.
Bay of Plenty Driving School owner Jeroen van der Beek said the decision to terminate a test was all about safety.
"At the end of the day, if the student's got an immediate fail error they've clearly made a reasonably serious mistake.
This is all about the safety of the testing officer. It's as simple as that."
He said the restricted test was divided into two stages. The first stage gave the tester the opportunity to decide whether they were willing to go onto the busy, faster roads with a student.
"You do get people, sadly, who are a long way short of being good drivers going for the test."
He said policy removed the decision on whether to carry on with a test from the tester.
Mr van der Beek said people sometimes came to the driving school after they'd had a test terminated.
Parents were often upset about the termination, but their children might not have told them the full story, he said.
Mr van der Beek said Tauranga was extremely lucky with the calibre of testing officers it had. They had a difficult job and were good, fair people.
According to the NZTA, the terminated rate for full licence tests in the Bay of Plenty was one in five.
Last year, nearly a quarter of restricted licence tests and 16 per cent of full licence tests were terminated.
In 2013, shortly after the restricted licence test was made more difficult, 37 per cent of Bay of Plenty people had their restricted tests terminated and 24 per cent had their full licence tests terminated.
NZTA said candidates could also fail a practical driving test by having it cancelled before driving started because they didn't have their licence with them, the vehicle wasn't roadworthy, or they weren't familiar with basic controls in the vehicle.
They could also be failed due to an accumulation of minor errors throughout the test.
NZTA national media manager Andy Knackstedt said pass rates for practical driving tests were also influenced by factors such as the road and traffic environment.
The most important determining factor for each person's likelihood of passing the test was how much that driver has practised and prepared for the test, said Mr Knackstedt.
The overall national pass rate for the more challenging restricted licence practical test had increased from 40 per cent, after its introduction in 2012, to more than 60 per cent currently.
"The Transport Agency's focus is on quality and consistency in testing, and therefore on ensuring safe drivers, not on pass rates," said Mr Knacksteadt.
Nationwide, 35 per cent of restricted licence tests and 27 per cent of full licence tests were terminated between January and September this year.
Sitting a restricted licence has a $48.20 application fee - with another $86.60 for the test. A full licence has a $49.60 application fee, with $59.90 for the test.
If you have to re-sit, you pay another test fee but not another application fee.