Every December, retail chains onboard a few hundred casuals for the Christmas rush. The people doing the onboarding are store managers.
Not payroll. Store managers.
A store manager onboarding a 16-year-old casual into Deputy doesn't think about the fact that the Retail Award has six junior rate tiers, each a different percentage of the adult base, and that the template they're copying from might be from last July before the FWC rate change went through. The casual loading is probably right. The base rate might be right. But the derived values, the ones that cascade from those inputs, are where it falls apart.
Public holidays are the obvious one. December 25. December 26. January 1. Three public holidays inside seven days. Under the Retail Award, casuals get 250% on public holidays, not the 225% that permanents receive, because the 25% casual loading is added on top of the base penalty. If payroll is configured at 225% for casuals, every single public holiday shift is underpaid. Across 200 casuals working Christmas rotations, that's not a rounding error.
Then the state problem. Boxing Day is a public holiday in most states. Not all. South Australia observes Proclamation Day on December 26, and Christmas Eve is a separate part-day public holiday. WFM systems need per-state configuration for this, and most templates are set to one state's calendar, which means a chain operating in three states with one holiday calendar is underpaying in at least one of them and has no idea.
Overtime thresholds are quieter but just as dangerous. Casuals working extended hours during the rush hit overtime triggers that differ by day of week. Saturday overtime under the Retail Award calculates differently from weekday overtime. A casual working a 10-hour Saturday the week before Christmas might be owed overtime that never gets flagged because the configuration assumes an 8-hour weekday trigger across all days, and nobody reconfigured for weekends.
What if a casual turns 17 mid-December? Rate should change. Most WFM systems don't auto-trigger rate changes on birthdays. So the rate stays at the under-16 tier until someone notices.
Nobody notices. Not during the busiest trading period of the year.
These errors don't surface in December because the payroll team is on reduced hours, the people who understand award configuration are on leave, and the errors compound across every pay run for six weeks while no one with the expertise to spot them is looking. By the time the payroll team returns in January and starts reconciling, the underpayment has been running since the first casual clocked on in late November.
The fix is always the same. Weeks of manual reconciliation. Back-pay adjustments. A quiet conversation with the CFO about exposure. Every one of these errors was detectable on the first shift, if anyone had compared what was configured against what the award actually requires. Nobody did. The people who configure the system in December aren't the people who understand the rules.