XAU liquidity sweeps cluster at session hand-offs: the pre-London probe from 06:00 to 07:00 UTC, the London open from 07:00 to 09:00 UTC, and the New York overlap from 13:30 to 16:00 UTC when US flow tests the London high or low.
Sweeps printed in the New York afternoon and at the 21:00 to 23:00 UTC rollover lack the liquidity for the reversal to travel, and rollover wicks are frequently spread artefacts rather than real trades.
Around scheduled US releases gold sweeps both directions within minutes with heavy slippage, so the pattern is untradable there despite looking identical on the chart.