What makes a strike dog?

The term strike dog originated in the coon dog world where whatever dog opened up on a track first was called a first strike dog & that carried over into the competion hunts. In nite hunts if a dog opened first the owner would say strike Sam & he would get 100 points for striking first. This of course is the short version.
It carried over to bear hunting with dogs striking off the rig or leash when dogs smelled bear. To me strike dogs simply mean dogs that open when they smell game. Of course there are a lot of good cur dogs & hounds that do not open when they smell hog sign but that does not mean they cannot go out & trail the hog up.