I find it astonishing how members of one religion sees the flaws of other religions by using reason and logic, but then cannot see any flaw in their own.
A and B are members of two religions and try to convert each other. A says B's religion is false because of x, y, and z. B says A's religion is false because of p, q, and r. Neither converts. An atheist, C, comes along and says both A and B are correct. Everybody goes their separate way smiling with victory.