Helsinki records zero traffic deaths for full year

"More than half of Helsinki’s streets now have speed limits of 30 km/h."

This is the only secret.

People over speeding is what kills.

Drivers are actually calm in Helsinki, not constantly honking and slowly rolling into you in the pedestrian crossing either.

Other places have introduced the same limit and haven't seen the same results.

People who are likely to have crashes are likely to be able who ignore the limit. One of the biggest problems in modern policy-making is the introduction of wide-ranging, global policies to tackle a local problem (one place that introduced this limit was Wales, they introduced this limit impacting everyone...but don't do anything about the significant and visible increase in the numbers of people driving without a licence which is causing more accidents...and, ironically, making their speed limit changes look worse than they probably are).

> People who are likely to have crashes are likely to be able who ignore the limit.

... which is why you have to do actual road design. You can't just put up a speed sign and hope people will magically abide by it. Roads need to be designed for the speed you want people to drive. When done properly the vast majority of drivers will follow the speed limit without ever having to look at the signs, because it'll be the speed they will feel comfortable driving.

It isn't road design, it is behavioural/cultural. People will drive recklessly when they do not care, for whatever reason, about the people they may injure by doing so. That is it. If you look at comparisons between countries, it is clear that means are different.

I disagree, idiots are everywhere.

The thing is, the vast majority of people - regardless of culture - have some basic sense of self-preservation. Speeding is easy when that 30km/h road is designed like a 120km/h highway. Speeding is a lot harder when that 30km/h road has speed bumps, chicanes, bottlenecks, and is paved with bricks rather than asphalt: if you try to speed, it'll quickly feel like you need to be a professional rally driver to keep your car under control.

Deliberately making roads "unsafe" forces people to slow down, which in turn actually makes it safe.

That's true. I stopped riding the bus because the road to the stop had big speed bumps put in, and it turns out distracted drivers fly off the road when they hit them, and one near miss was enough to make me drive instead (sure it's a cognitive bias, but it's enough to make me pick the more convenient option). One fewer pedestrian means one fewer potential pedestrian death!