I have only gotten the average twice - the first year I started working and the year I only worked half the year and studied full-time.My daughter is one who gets the 'average' tax refund. But she claims for Motor vehicle travel costs almost daily, plus required phone use etc.
It normally all comes down to the job, and the costs you incur as part of the job.
Almost 1 in 5 people get no rebate. Some get many thousands.
Not working for part of the year can also cause a refund of tax overpaid at margin rates.