> Ideal would be speed limit based on the road. You kinda already have that, but you cannot make it too confusing for drivers. German example for roads betwee

> Ideal would be speed limit based on the road. You kinda already have that, but you cannot make it too confusing for drivers. German example for roads between cities: No sign at all, default speed limit 100. 70 sign (usually with a reason e.g. winding road, trees etc). 50 sign or even 30 sign, no overtaking sign, e.g. narrow road, pot holes, intersections. Works, but can be quite stressful to keep track of particularly for new drivers. Issues with that: The locals who drive 80 will complain that there is no reason for a 40 sign and laws tend to require a reason (e.g. speeding tickets are cancelled retroactively if the state cannot justify why there needs to be a limit). Too many signs and cases confuse drivers and are easily missed. Installing, replacing, repairing and keeping track of signs is expensive. Too many rapid adjustments also don't work well with slowing down, accelerating, reading signs etc., so it cannot be too fine grained. That is why there are "one speed for those type of road fit all" approaches: to keep matters simple.