do people repost them again or something wrong with my computer?
ex. i've seen that "new body kit" for enough of times already!

 

Each new post starts a thread and has a date of origin-just check the date of the first entry.
Then over time that thread goes lower in the line of items on MCO. But if someone finds it later and then posts a new addition then that "old" thread becomes active and reappears at the top of the list of current topics. Once no one is posting more info about any of these threads then it will fall back into the hidden archives of posted items.