I have in the past ask Mick the farmer were are horse are kept WHY does he use Barbed wire...(Being an American invention and brought back to england)...Farmers just don't seem to know if you ask me...
I think it was the easiest thing to keep cattle sheep in check before electric fencing came along (it has a similar effect, only potentially causing actual injury instead of just a shock) . Problem is, it's much cheaper for farmers to just keep the old barbed wire instead of replacing it with leccy fencing
The worst is when the fencing has collapsed and the wire is partially buried