1. O próprio Q respondeu à sua pergunta no episódio 16 da segunda temporada quando ele enviou a Enterprise para encontrar o Borg pela primeira vez - "Q Who".
"The Borg are the ultimate user. They're unlike any threat your
Federation has ever faced. They're not interested in political
conquest, wealth, or power as you know it. They're simply interested
in your ship, its technology. They've identified it as something they
can consume."
— Q, commenting during a senior staff briefing
Os borgs não vêem a federação como uma ameaça, nem estão impressionados com eles como uma sociedade. Eles simplesmente querem sua tecnologia e não têm nenhum problema em enviar um cubo de milhares de anos-luz para obtê-lo, especialmente porque sabem que a Federação representa pouca ameaça para eles.
2. Vários anos depois, durante o período de tempo "Star Trek - First Contact", os borgs aprenderam que a Federação não é tão fraca quanto pensavam inicialmente, e têm algo mais a oferecer, então apenas tecnologia. É por isso que eles voltaram no tempo para tentar assimilar a Terra e a humanidade no passado.
BORG QUEEN (OC): What's wrong Locutus? Isn't this familiar?
BORG QUEEN: Organic minds are such fragile things. How could you forget me so quickly? We were very close, you and I. You can still hear our song.
PICARD: Yes, ...I remember you. You were there all the time. But that ship and all the Borg on it were destroyed.
BORG QUEEN: You think in such three-dimensional terms. How small you've become. Data understands me. Don't you, Data?
(Data is standing in a Borg cubicle)
PICARD: What have you done to him?
BORG QUEEN: Given him what he always wanted, flesh and blood.
PICARD: Let him go. He's not the one you want.
BORG QUEEN: Are you offering yourself to us?
PICARD: Offering myself? ...That's it. I remember now. It wasn't enough that you assimilate me. I had to give myself freely to the Borg, ...to you.
BORG QUEEN: You flatter yourself. I've overseen the assimilation of countless millions. You were no different.
PICARD: You're lying. You wanted more than just another Borg drone. You wanted a human being with a mind of his own, who could bridge the gulf between humanity and the Borg. You wanted a counterpart, but I resisted. I fought you.
BORG QUEEN: You can't begin to imagine the life you denied yourself.
PICARD: It's not too late. Locutus could still be with you, just in the way you wanted. An equal. Let Data go and I will take my place at your side, willingly without any resistance.
BORG QUEEN: Such a noble creature. A quality we sometimes lack. We will add your distinctiveness to our own. Welcome home, ...Locutus. ...Data, you are free to go.
Referências:
Sinopse "Q Who" da Memória Alfa
"Transcrição do filme de Star Trek - Primeiro contato" de chakoteya.net