Yeah, that just means the later parts of the animated gif (not actually a video) are not finished loading yet. I see that a lot with the longer ones, especially on this site where there may be 7 other moving gifs on the same page.

Basically the gif is playing through faster than it is loading. You may also notice that each time it cycles through, it plays a bit longer before restarting. When it is completely finished loading, the distortion effect will be gone.

You can just wait, but there's a more efficient way (particularly if you'd like to keep surfing while the memory-hogging beast finishes loading):

If you mouse over the top-right corner of the page, a hotlink called "Link to the gif" becomes visible. right-click on that and select "Open link in a new tab". You now have a new "page" that is not trying to load anything else but that one moving give. When the busy icon stops spinning, it's ready to watch. ;)
Hinoron Hinoron16.01.201708:02responselink
That's fair. ^_^
Hinoron Hinoron 15.01.201719:11 response link
Interesting if you stick around to watch the whole thing. So what's this experiment demonstrating? Gravity on very small bodies?
Hinoron Hinoron15.01.201710:43responselink
Um... How many of those fish do you suppose are stunned to death immediately on their high-speed impact with the water from that height and velocity?
Hinoron Hinoron15.01.201710:40responselink
Clearly, neither of them works in Communications.
Hinoron Hinoron 15.01.201710:39 response link
Overreact much? The kids are watching you, you spaz!
Hinoron Hinoron 15.01.201710:38 response link
That... would actually be something that would reduce the number of pedos tempted to go after real boys, come to think of it.
There's like 1/10,000th as many in reality as the news would have you believe, but still...
Hinoron Hinoron 15.01.201710:37 response link
I feel like this would be funnier if we had a splice of what the guy is seeing through his goggles in the corner. As it is, it's basically just a guy flailing a bit.
Hinoron Hinoron 15.01.201710:35 response link
It doesn't even look like it has functional eyes. Are we sure this is real?
Actually it probably is. Ironically, someone making a fake would have made it look more realistic. :/
Hinoron Hinoron 15.01.201710:32 response link
Thank you Alanah, for making the Internet a better place!
You may also have contributed to the murder rate of minor boys by their parents... but overall, a net gain! ^_^
Hinoron Hinoron 15.01.201710:30 response link