Yoga and daily life involve a lot more pushing movements than pulling. For example, you are often pushing the ground away in poses like Plank, Downward-Facing Dog, and Crow or pushing a stroller, shopping cart, or lawn mower. However, there are few opportunities in asana practice to pull against load or your own body weight.
When you only practice pushing movements with the upper body, you end up strong in one direction and conversely weak in the other. Prevent muscular imbalance, tension, and injury, by adding more pulling motions to your practice. These Dandasana Slides with a yoga blanket are a great way to start.