It is caused by fact that you are displaying articles as a link list instead of article list - links list have only three elements: image, header and text.
Then I don't understand why one of the options to turn on in Links is "Display Readmore" and when you mouse over the option it says "You can display readmore for the links".
That "readmore" is a link placed under all links on the list - it is not a link for every item, but one readmore link for all links which can lead in example to category with more items.