Inspectors may investigate individual complaints but their focus is on wider workplace activity and where there is evidence of repeated breaches of employment standards, the MBIE inspector told me.
They pay particular attention to agreements, wage records, and leave and time records.
The inspector told me casual agreements were particularly problematic. I expect this has something to do with how busy we're all getting. Growth means more work, so you might rely on casual staff more often.
A casual worker has no guaranteed work or income, and the work they do cannot be anticipated. This is sometimes confused with part-time employment so it's a good idea to review any casual contracts you have to ensure that's still the most appropriate type of contract for that worker.
This is for the business owner's protection as well. If a "casual" gets paid 8 per cent holiday pay and it turns out they actually qualify as a part-time employee, they may be able to recover additional paid holiday leave from you after 12 months.
If you're not sure about any aspect of your workers' contracts, ask for expert advice. That will mean no nasty surprises down the line.