Cats definitely have preferences
I tried the Hill's Senior 11+ to see if our two 14 1/2 year old Burmese cats liked it. They didn't like this food at all. I tried it a few times over the course of 3 days - each time they sniffed it & walked away. I waited a week, then tried it again. They still didn't like it. Also, the food itself once opened & in the bowl has quite a pungent smell. Our cats prefer the Royal Canin Aging food. They always eat it, never turn their noses up at it and it does not smell like the Hill's.