Have you ever noticed how the loudest meeting, the biggest shock in a budget or the wildest public reaction eventually quietens down?

That’s not just wishful thinking, it’s a statistical reality: regression to the mean.

Extreme events tend to be followed by more ordinary ones, things revert (or regress) toward their long-term average.

We see this everywhere, in human behaviour, in politics, in community life. And last month’s Kiama by-election gives us a vivid local example.

Earlier this year, the seat of Kiama was thrown into chaos when the sitting MP, Gareth Ward, was found guilty of sexually abusing two men.

He resigned just as a vote to expel him from NSW Parliament was about to occur, which triggered the 13 September by-election.

Labor’s Katelin McInerney won decisively with about 37.32% of first preferences, with a two-party preferred share of 60.19% vs 39.81% for the Liberals.

Meanwhile, the Liberal candidate saw a swing against the conservative vote of about 14.48 points in primary votes.

What’s striking is how that result reflects a reversion from the extreme circumstances surrounding the vacancy.

The scandal and succession of events pushed the electorate outside its usual voting patterns.

But once the by-election was decided, things look more like a return toward the underlying political tendencies in the area.

Analysts caution that comparing swings in such a seat is tricky. Ward had held the seat as an independent after leaving the Liberals, and his personal following distorted the baseline.

But the upshot is clear: the extraordinary conditions that preceded the election were unlikely to sustain forever. Voters gravitated back toward more stable alignments once the crisis passed.

I think leaders also need to consider when the mean itself is moving.

Sometimes what seems like “returning to average” is actually a shifting average.

For instance, demographic change, evolving attitudes, or sustained external pressures can shift what “normal” means.

In Kiama’s case, the scandal forced a momentary deviation, but the long-term leanings of the electorate remain relevant.

Extremes should be regarded as wake-ups, but we shouldn’t assume permanence.

If a campaign, crisis or public mood runs extremely one way, treat it as a cue to dig deeper, not as a permanent realignment.

In Kiama today, the extreme disruption brought on by Ward’s scandal gave way to a more stable outcome, a seat firmly in Labor hands, but not as a reactionary anomaly so much as a firm return to equilibrium.

That doesn’t mean nothing changes. It means change often overshoots, then swings back toward the centre.

Maybe the next time you see an overblown reaction in a meeting, or a headline that feels too big to last, you can smile and whisper: “That’s regression to the mean doing its work.”