It can be many reasons. One of the number one reasons for me was I was terrible at Story Titles and taglines. I begin practicing for example,

Asking questions in my titles and tagline

Using numbers in your titles

The "when" statement: "When your stories become a message, " "When love won't let you in.

If you can write a good title, good tagline, and good opening paraph, you will capture the reader and persuade them to continue reading your story.