What benefit does symmetric encryption have over asymmetric encryption?

Symmetric encryption is typically faster than asymmetric encryption. This is why many protocols use asymmetric encryption to exchange a symmetric key, and then use that key for the rest of their transaction. It is not more secure, key length is not a meaningful difference between symmetric and asymmetric encryption, and key distribution for symmetric encryption is more challenging for larger populations using symmetric encryption if confidentiality needs to be maintained because every potential pair of communicators would need a different symmetric key.