"Why guardian dogs?"
Guardian dogs are effective protection from predation.  Working with guardian dogs allows us to keep small livestock safely.

Guardian dogs, unlike donkeys and llamas, are nocturnal, like most predators.

Guardian dogs alert us to other problems, like shorts in electric fences, a snake in a pasture, or a kid outside a fence.

Guardian dogs create territory by barking and marking.  When there is a sufficient number of dogs for the conditions, predators go around.  Don't believe it?  Call me, I'll swap stories with you.
 

"How many dogs are required?"
Safety first.  The number of guardians required depends on a number of factors, including: age, experience and condition of the dogs; known and anticipated predators; size of browsing/grazing area; topography; the type and amount of vegetative cover and weather or other special conditions.

We want our goats to be safe, our dogs too.  We are also interested in preserving the natural wildlife role of predators. 

When in doubt, opt for more dogs!