Observation, spacing and changing road conditions
Stopping requires detection, a decision and controlled braking. During the reaction interval the vehicle continues to travel; during braking the available grip and vehicle condition influence the distance required. Greater speed therefore reduces the margin for a hidden pedestrian even before any numerical stopping calculation is made. Following space should allow for the actual view, surface, load and behavior of traffic rather than a fixed gap copied without context.
Rain, road paint, debris and standing water can reduce usable traction. Make needed speed reductions before the difficult section, use smooth inputs and avoid combining an abrupt turn with heavy braking. Fog and glare can shorten the visible stopping distance. Select appropriate lighting, increase space and slow enough to respond within what can actually be seen. High beams reflected by fog do not restore a clear view.
Anticipate conflicts rather than predicting that others will behave perfectly. A truck may need extra turning room; a stopped bus can hide a crossing person; a ball can be followed by a child. Avoid remaining beside large-vehicle blind areas. Fatigue, distraction, alcohol and impairing medicines reduce observation or control, and schedule pressure does not remove that risk. Stop lawfully for rest or phone adjustments. Equipment failure calls for controlled deceleration and a safe stop, with qualified inspection when safe operation is uncertain.