From Wikipedia:
In modern usage, the practice of charity means the giving of help to those in need who are not related to the giver.
Now, what does that paper write about? First, they consider "spiritual help" the greatest help one can give. Yet the vast majority of the people doesn't need that kind of help, so per definition that's not charity. If I give a pair of shoes to someone who just had both legs amputated, you won't really call me a charitable person will you? As we know very few of the baptized are new converts, most are born-ins, from which we can conlude that the people don't really want any help from JWs, no matter how much it's stressed in the literature that they are weary and in need of spiritual leading. They are not.
Second, charity is help given to someone "not related". JWs consider each others as brothers - and if we take their words for it, they fail on the definition again. They do extremely little for the not JW ones. As a parenthesis I read on this forum that when they help a JW to rebuild a house after a catastrophe, they ask the money back when they get it from the insurance or the state? Can someone confirm this maybe with some proof? Because if that is true, then the JW charity indeed converges to 0.
Third, they fail the Bible's interpretation of charity too. Mathew 6:2: "So when you give to the needy, do not announce it with trumpets, as the hypocrites do in the synagogues and on the streets, to be honored by men. I tell you the truth, they have received their reward in full." On the very small occasion they do help the outside needy ones, they blow the trumpets, and give wide publicity to it in the literature.