If Scientology has 8 million members (ha!), and 1300 have made it to OT 8 (not to mention that it actually goes up to OT XIV), then that means only 1 in 6000 Scientologists have made it to Total Freedom. Or rather, have learned that "now I know who I am not."
Would you spend hundreds of thousands of dollars for a one in 6000 chance to reach the top of Scientology? All it takes is money and time, yet only 01625% of Scientologists have done it since 1987???
Now if you use the 50,000 figure of membership that many critics think is accurate, then that's 2.6% of all Scientologists making it to OT 8. And what of the point that Scientology said "oops, our OT 8 that Hubbard himself wrote is a bit messed up. You'll have to take it again properly."
Since 1950 Dianetics and Scientology have been changing. Even after Hubbard died, it's still morphing. And it still doesn't produce Total Freedom, whatever that's supposed to be.