I obviously don't have a in depth knowledge of Finnish rail, but have you ever looked at rail in the US? I can show you tracks with completely missing ties. Tracks that move vertically by a foot when the train goes over them. Tracks that visually snake all over the place. The difference is made by slowing down the train. Derailment at 3 mph rarely matters. The biggest risk is the conductor doesn't know it happened & continues to drag the car along the tracks