Depends. If there is even a shred of truth in what Lore had to say, the colonists wanted a 'less human' android.
As to why would Data aspire to be more human? He was surrounded by them, his 'father and mother' were human, plus he held the memories of the human colonists within him. And that's just scratching the surface.
Thought of something else. It is most likely that he was programmed that way. Why else would Soong have worked so long and hard to create an emotion chip for Data? Why would he have built him with a dream program? I believe he was designed to evolve and find his own version of humanity.