Pros and cons. I believe in Romania, where brown bears are very prevalent, aggressive dog breeds are used to protect sheep... But they are so aggressive that they pose an overall greater risk to humans than the bears themselves: https://romania-mountains.com/shepherd-dogs-in-romania-what-...
KBD’s are a hunting dogs. They hold bears in place with personality and it is common for them to work alone.
In North America, they are used to “shepherd” bears away from human habitats.
For example in the US Park Service link, you can see a single dog riding with a single park ranger.
That's why they're called lifestock guardian dogs. Romanians don't have a proper word for it, they're called "shepherd dogs". Bad description. Shepherd dogs like Border Collies herd sheep. The lifestock guardian kind fend off bears, wolves and hikers alike. They're very territorial and their territory is wherever the livestock happens to be at that point in time. The native breeds are usually manageable, while the Caucasian Shepherd and the Kangal are not, at least not without shouting, stick waving and throwing rocks at them. The Carpathian "Shepherd" Dog is now exported to Italy to fend off wolves.
For example in the US Park Service link, you can see a single dog riding with a single park ranger.