Even if you hate Elvis' music (which is an odd statement, being as it varies so incredibly, encapsulating a wide range of genres), it can't be ignored that the man had passion, and put his heart and soul into even the throwaway tracks he (too often - thanks Col Parker) sang.
That's what I love in a singer - the sense that they're feeling the words, the meaning of a song. They may not have written the song, but they can often better realise the songwriter's intentions than you'd imagine, and/or raise something quite ordinary into the extraordinary.
There were and are more technically adept or lyrically sophisticated performers around, but so often they leave you cold as there isn't that emotion...
Clare Newsome is Editor-in-Chief of What Hi-fi? Sound and Vision