My shelter cat was sick with a URI when we got her and wouldn't eat. I tried sardines, tuna fish, yogurt, milk, raw chicken, chicken stock, cheese, and every other cat delicacy I could think of. The winner was the gravy from Fancy Feast (she just licked the gravy off the top, poor little thing was too sick to chew.)
Once she got better we switched her to dry food, and after a few months of just dry food I noticed her coat was dull and full of dandruff. We re-introduced Fancy Feast and she's shiny and lustrous again! She goes crazy crying with excitement when she sees me bring out the can and will do cat parkour backflips to get to her food bowl. Our dog loves licking out the cans too -- although his sister now never leaves leftovers.