Perth learner drivers hoping to sit their practical test could be in for a long wait as a backlog forces them to fight for a cancellation spot – or book a test in two years’ time.

Drivers who are not exam-ready are being blamed for clogging up the system, along with a shortage of assessors across WA.

Steve Kolb, Driving Instructor at Drive Perth told Ian Blackley, filling in for Jo McManus that it's much cheaper and quicker to let your driving teaching assess you.

"We know whether you are going to pass or fail and then just don;t do a driving test because every time someone fails, it just adds to that queue," Mr Kolb said. 

Figures released to WAtoday revealed the metro area’s busiest centre Kelmscott, also had the highest pass rate for students at 44.6 per cent.