why has he waited so long after Adam and Eve.
Yes, why ? Supposing that Jehovah's purpose, in order to straighten up the messy situation where our first parents had left us, was to send His son for this redeeming sacrifice that is part, we are taught, of His perfect justice. Then, He could have cleared the earth of all wickedness after Jesus's resurrection and a reasonnable time for the good news to be preached over the earth. At that time, the earth, statisticians tell us, comprised about 200 million people (50 million in the whole roman empire, they say). If we enter into the JW's logic, He would have destroyed , say 180 million evildoers (or ignorant of the good news...). Now that He has waited 20 more centuries, the toll will be 6 billion. And for what extra benefit ? The one who knows the answer is, indeed, very intelligent, but we can confidently assure that even the most literate person doesn't know more than the most ignorant on that ground. Not knowing is part of our human condition, we have to make do with it until, Jehovah willing, He let us know, maybe. For the time being, all that I know is that I know nothing. But at least, please, let JWs spare us with their non explanatory childish explanations that don't pass the most elementary reflection.