> if one packet is dropped or smashed, there is a higher probability of following ones to meet the same fate.

Not necessarily. I am not an expert on this topic, but I believe physical device failure is one of the least common reasons a packet is dropped (at least on physical cable transmission). I think link saturation, priority routing (for certain types of packets, or contractual reasons) might be more common. There are thousands of routers out there with a variety of different configurations that decide which packets go through under which conditions.