matoo: old hides
To count goats that are elsewhere is to count those that are (dead and all that remains is) nothing but hides.
In communities that practise livestock herding, sometimes animals go missing as they are pastured. It is common practice, therefore, to take stock by counting the animals when they return to their enclosures.
One who places reliance on things that are uncertain runs the risk of disappointment when the outcome turns out unfavorably.