Differences between various embedded youtube links, why?

[jc1240]

Some youtube videos on the forum have a butt on to watch directly on youtube (something I often like to do so it shows in my history and I can copy the URL). Others don't and I have to start the video to get the link. Why? Here is a screenshot of 2 videos from a single post with the top one having the button/link to which I am referring.

 

[Sticky]

I think it depends on how they are embedded in the post. There is more than one way to post a YT link on forums.