If your Facebook friend list contains more than a thousand friends, or possesses an exploded friend list, it's pretty confirmed, that you could not see some friends' posts of recent statuses, life-happening, photos etc.
When you could not see them, you neglect the fact because you do not even know the fact exists.
When your purpose to have a Facebook account is to reconnect with oldest friends and long time friends who are thousand miles apart from you, all their life-going-ons are no longer your concern.Their posts might be wiped away when the other half of your friends in the list excessively update their self-obssessed, self centred, and even things those are not worth to be seen on our homepage.
So, I removed some of the unknown friends from the list to reduce the amount. I'm sure that they and I do not share any friendship. Sorry for those who have been removed.