This tool lets members of a group contribute money without other members of the group knowing how much they contribute. But, it lets everyone know how much of the needed money has been contributed.
For example, the members of John's Bible study group want to contribute $500 to the ministry of Joshua in Jersey, but they don't want each other to know how much they each plan to contribute. Jerry, who is wealthy, doesn't want to look like he is showing off. Janice, who is just making ends meet, doesn't want to be embarrassed by the little amount she can give. And Jay isn't going to give at all; he'd prefer to give to something else.
So, they use this tool, and everyone knows when they've reached $500 and nobody knows how much another person is (or isn't) giving. Then they all - separately - send their money to Joshua's ministry account and nobody in the group knows anything they don't need to know.
But when you give to the needy, do not let your left hand know what your right hand is doing, - Jesus (Matthew 6:3)
“Whatever we find lovely in a friend, or in a saint, ought to elevate our affections: we should conclude that if there is so much sweetness in a drop; there must be infinitely more in the fountain. If there is so much splendour in a ray, what must the sun be in its glory!”
–Henry Scougal, The Life of God in the Soul of Man