Citing your references can be time-consuming, but here's why it's important:

1. Citing your sources helps you to avoid plagiarism. 

2. Readers can go back and look at your sources if they'd like to follow up or read further. 

3. By demonstrating how widely you've researched a topic, your own argument ends up being more credible.  Citations can show you've considered a wide variety of opinions when forming your own argument. 

4. Citing is standard practice in academic conversations.  Scholars have been debating ideas through written works for years and citing is a way of respecting those who've engaged in the topic before you. 

 Based on UCLA's Why Cite? guide.