There are different possibilities that make the videos load slowly. Slow Internet connection speeds are a common issue in some cases. Also, using Internet Explorer instead of Firefox can cause videos to load slower than usual. But the most common reason is the source file.
Since we do not host the videos, they get streamed from third-party websites which usually reside in China. Due to the heavy traffic that these sites experience, loading speeds become extremely slow during Chinese peak hours. Sites like Toudu, Youku and 56.com are the three major chinese based websites that stream movies and videos. In case you see that these websites are the host of a video, the best option is to give the video some time to load, so you can enjoy watching the entire video without lagging or interruption.