Please note that the “percentage of people”, “number of seconds” and associated video image could vary —so you should be careful about all similar messages. Now the simple thing is: these messages are spam and you should not click on the associated “video”. The fact is that the associated video is not a video at all. What you see is actually a thumbnail picture that looks like a attached video with a Facebook message. The message and the picture are chosen to make you curious and give click. DO NOT DO THAT and delete such messages right away. But what happens if you do click on the given link? A click on the given link will take you to a scam website. The website might look like a Facebook page or anything else –but don’t be fooled by this stuff. If you will click on such links the spam may simply spread itself (i.e. your friends will receive similar messages from your account) or it may even compromise your own Facebook account. Facebook has been target of a variety of scams. Nowadays, another “emoticon” scam is doing rounds that asks people to follow certain malicious instructions. Following these instructions may compromise your FB account’s safety. So, be careful while you’re on Facebook.