What is the meaning of linkdown in docker0 Linux Route

Question

I have seen this already, and understand what linkdown means.

However, for the interface of docker0 running on two of my computers, I have two different cases.

Case 1 linkdown with DOWN

$ ip link show dev docker0
6: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default 
    link/ether 02:42:b3:23:3f:f9 brd ff:ff:ff:ff:ff:ff


$ ip route
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown

Here, we see that docker0 is indeed down and has the linkdown in routing entry.

Case 2 No linkdown while DOWN

$ ip link show dev docker0
6: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default 
    link/ether 02:42:77:ed:9f:ff brd ff:ff:ff:ff:ff:ff

$ ip route
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 

Why do I have both of these cases? Pinging after setting up a docker container still works?