I think he is a "man on a mission"...to destroy humanity .

Come to think of it Riddly Scott likes people going mad and killing each other in general...look at " The Terror".

"The Stars are better off with out us!" [THE EXPANSE]

I thought it was pretty clear already in Prometheus.

Pretty much the moments after he cut hes hair. Specifically when he started fingering with his clone and told that Weyland wasn't worthy of his creation. David, obsessed with the act of creation that had value in its end, uses any means available. It is remarkable that no one from the remaining crew has questioned imposter Walters’s identity and just carried on like the worst was left behind.

Ending was just Riddleyculous

@StrongPine said:

Riddleyculous

Well the humans were mostly stupid and acted in a illogical manner, unlike the original Alien. But I liked the premise of the film and the mad as a hatter robot. Less action, less CGI, more horror, and this could have been pretty good