system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why don't nerves regenerate like nearly everything else in our bodies, especially if they're so important?
gpt
If they regenerated, they would lose their connections with each other, which is arguable what makes you, you. If you could somehow regenerate nerve tissue in your brain, you would forget pretty much everything in that region and it would be like dealing with a newborn for those functions. 

For non-cognitive functions, it might not reconnect properly and not work anyway; it would receive/send signals, but perhaps not in the way that your brain expects them to. 

Peripheral nerves can actually regenerate function to some degree, but CNS nerves are static for a reason.