Nearly 30,000 drivers have been road on a provisional licence for up to 30 years.
A midlands driving instructor says the incentive to sit a test simply "isn't there."
More than 28,000 drivers have been on the road with a provisional licence for up to 30 years.
Figures from the Road Safety Authority show they're on their third or subsequent learner permit, and haven't sat a test.
However, the number who've never sat a driving test could actually be higher, as the stats from 1994 to 2008 don't include testing data.
Michael Hogan from Hogan's School of Motoring in Portlaoise, who's also a former Garda, says the chances of getting caught are "slim to none:"
These students say there are long waiting lists for driving tests:
Editor of CompleteCar.ie, Shane O'Donoghue, says thousands of learner drivers have been taking advantage of the system loophole for many years: