Why does this happen on facebook?

[Ruairi]

I make a status update and just say 20 likes. When I go to see who liked it 19 of those popped up in a list. However, there was one missing. Also, it was my birthday recently and I received say 30 posts on my wall. When I clicked for a list of people who'd posted on my wall it only showed about 25 of these posts. I know it's not a big deal but I wanted to go through and say thanks to those people and now I just left 5 blank without replying. It looks like I'm shunning them or something. I'm on mobile Facebook btw. If that makes a difference

[Lizhaa]

Maybe the page didn't upload right, or they made a mistake

[abraXus]

it just means they deactivated their account after liking it... or facebook suspended their account for some reason

[M]

Their account is inactive and has been since they posted the birthday message.