Avalanches can reach speeds of 80 mph within about 5 seconds and each year avalanches kill more than 150 people worldwide. That is why we learn about avalanche safety and what to do if an avalanche does occur. Statistically if a victim can be rescued within 18 minutes, the survival rate is greater than 91%. The survival rate drops to 34% in burials between 19 and 35 minutes. So speed is critical in avalanche rescue.
Watch this video from BCA about beacon searching.