Packet Loss
Packet loss occurs when one or more packets of data travelling across a computer network fail to reach their destination.
I actually learned about this when playing Valorant haha.
One reason this can happen is that the packet contains an uncorrectable bit error and therefore has to be discarded.
A more likely reason, however, is that one of the nodes that has to handle the packet—for example, a switch that is forwarding it from one link to another—is so overloaded that it has no place to store the packet and therefore is forced to drop it. This is the problem of congestion just discussed.
Less commonly, the software running on one of the nodes that handles the packet makes a mistake. For example, it might incorrectly forward a packet out on the wrong link, so that the packet never finds its way to the ultimate destination.