Occasionalists believe that in order for cause and effect to work, God has to intercede. This rather elegantly deals with a whole load of theoretical problems around causal realism.
If you were an occasionalist, you might think, if such a thing as a 'god-of-the-gaps' exist, it should be possible to build a device that mimics its powers, a 'god machine'. Such a device would be very useful.
Except, if occasionalism is wrong, and the universe simply doesn't work like that, it's obviously going to be totally impossible to build a machine that replicates the effect, or to understand how the effect could function.
What if consciousness is just another 'god-of-the-gaps', and we can't replicate it or understand it, because it's fundamentally a nonsensical concept?