system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Trek] Can the Borg innovate or can they only advance by absorbing the technological advances of other species?

Does the Borg have an R&D sector?
gpt
There are limits to the amount the Borg cannot innovate new strategy.  There is a queen, and the limit of the strategy ends at what the queen deems a good plan.  Because the queen has selfish reasons to remain alive, it limits the overall extent of the plans of the Borg.  

Meaning. 

Once the Borg has mastered time travel. 

Go back in time against the humans, Vulcans, Romulans, etc. Before those species are able to develop light speed travel and assimilate them now.  

The Queen wants to protect her own narrative and that limits the choices for the Borg to take further domination.