If you believe the Bible, Satan is out to deceive the whole world.
If you would agree that the theory of evolution is a lie and that a timeless God is a lie, then it is possible that a globed earth spinning at the speed 1000 mph and rotating around the sun at 67,000 miles per hour mph contrary to our earthly perception is also a lie.
The first is a theory, the second is a subjective opinion about theological realities.
The present consideration is an empirically knowable fact, only willfully obscured by the peculiar belief that the world has entered into a generational conspiracy for no apparent reason.
That reason is what you were asked for.
Satan does not want us to believe the Bible to be true, so when he attempts to take over the world the masses will not recognize him for who he is.
Nothing in the notion of spheres and a spherical world, etc. is problematic in relation to the Christian faith, which is why most Christians (especially those with a science background) understand and accept the reality you need a conspiracy to negate.
The second coming of Christ will probably be explained as an invasion from "outer space".
By whom? I mean, given the narrative, that would be a bit pointless.
The Bible has been turned into a myth by Augustine, Copernicus, and Darwin.
The first two would be laughing their keysters off at you, being Christian. The last? Certainly some have attempted to use his work to do that. I don't believe they've remotely succeeded. Why do you?
Lastly, none of that really answered his question about motivation.