The JW's teach that they are the only people who are in God's favor and only they will be saved at Armageddon. They teach that pastors and preachers are corrupt getting rich from preaching. They also point out how some pastors or preachers commit horrible acts and so all of them are evil. They lump all of Christians into a category called Christendom while pointing out all of the bad things done by Christendom. Then they claim that JW's are not like that. It's a convincing argument to get people to join them but there are a few flaws with this reasoning.
This is a logical fallacy known as stereotyping. You take something that is true for part of a group of people and say it is true for the entire group. It is true that there is corruption in Christianity with televangelists and some preachers getting rich, driving fancy cars. And it is true that some have committed horrible crimes. However, there are several preachers who are not getting rich and who are concerned only with teaching biblical truth, and who have not committed horrible crimes. Corruption of part of the group is not corruption of the entire group.
There is a second fallacy that is implied. They imply that since "Christendom" has greed & crimes committed in it while JW's don't (supposedly), then the JW's are the only true religion. This is an irrelevant assumption. The two aspects have no relation to each other. Many of the JW's teachings are not biblical (as I have pointed out in previous posts). I grew up in the JW religion and then left and became christian. I found out that Christianity is not this big bad evil religion that the JW's make it out to be. There are bad Christians and preachers, but there are far more good ones. All it proves is as Jesus said, Narrow is the path to salvation and few find it.