you must drive at the maximum posted speed in all conditions.

It is not required to drive at the maximum posted speed in all conditions. In fact, the legal requirement in many places is to drive according to the conditions, which may mean driving below the speed limit when necessary for safety. For example, in Australia, drivers must drive to the conditions even if that means traveling below the posted speed limit, reflecting a general principle that speed should be appropriate for the road, traffic, visibility, and weather conditions. Similarly, in Germany, there is a legal obligation to adapt speed to these factors and maintain control of the vehicle rather than strictly driving at the maximum posted speed. Thus, driving at the maximum posted speed is not mandatory in all situations; safe and appropriate driving speed depends on current conditions, and it is often legally required to drive slower if conditions warrant it. This includes considerations such as weather, traffic density, road conditions, and driver capability.