Well, think of what you have: an aggressive bully (Rutherford), leading a tax-free printing company (WTB&TS), and a world full of "spiritually hungry people" (the Great Depression) looking for answers. The people who work to expand your business are paid either peanuts (Bethel) or in a permanently out of reach carrot (everlasting life in heaven on earth).
You have "holiness" from persecution (1918-9 trial). You have a powerful, very established adversary who looks bad if they respond to your jabs or if they do nothing (Catholic Church).
Now I ask you--how could you fail to expand this business?? Hell, you make blunders in your print (1920, 1925), and people still want to work for your printing company!
And WWII, well that just skyrocketed them. The dubs had an aggressive man to get the ball rolling, and a bureaucrat (Knorr) to direct and manage the growth (Gilead, TMS, etc.).
Brain dead hit it dead on. All they needed was aggression....personal foibles aside, Rutherfraud was just the man the WTB&TS needed....