Discussion topic: Why do the Borg need to assimilate entire cultures to gain the features of their biological distinctiveness and unique technologies?
The Borg have transporter technology of some sort. They could easily abduct select people from orbit and leave, but instead they invade planets and assimilate every person. It seems highly inefficient to me.
I guess in a way it’s like a virus. They conquer civilizations. Catalog their technology and biology and use their industry to produce more borg to continue the process.