What Appeals to the Reader?

When we write something we expect somebody to read it. Most often we write about some message we want to convey. Do we also think of whether that appeals to the reader?

When I asked one of the readers of my blog, what I should write about today, I was surprised to hear:

Write whatever you like. But I don't want to see any picture other than a baby elephant.

So I searched for a baby elephant and found one on the site:
Big Babies at the National Zoo.

Along with the baby here you can see the legs and trunk of the mother. My message is the additional part. My reader will first look at the baby elephant and may or may not care for the rest of my message.

So whatever I want to convey I have to weave it around what my reader wants in such a way that the person just cannot miss it.

Have you got my point? Or you wanted a baby cub and fleeted past my blog without getting anything out of it?