Sonic is the wind. Freedom, independence, living life by your own rules, doing what you truly think is right even if the world tells you you're wrong. Disliking oppression and while not calling himself a hero lends a helping hand to those by his side. Being the gale of fate when the world looks like it's falling apart. If Sonic is the wind then Silver is the divine wind. An unknown force here to bring forth light in the darkness and he's here to help. If Sonic is heroic then Silver will give everything to give people a chance at a bright future, including Sonic himself. The very nature of this means that Silver comes in to help Sonic when he "failed", even if that's not the intention of Sonic Team, as they want Silver to have a chance to be another valued friend of Sonic and his world