You will be given a definition of a task first, then some input of the task.
You are given a sentence and a question. You're expected to write the correct answer based on the sentence.

Sentence: One of Sarah's neighbors spilled dog food all over the stairs. The dog food pieces are on three stairways and all over the landings. Sarah gets mad and kicks a piece of dog food. The dog food flies across the wooden planks from one side of the staircase landing to the other. The dog food reaches the neighbor's door mat. It moves a few inches across the doormat. Question: Why didn't the dog food move further across the doormat?
Output:
The door mat is a spikier surface