How do people change their profile pic on Facebook without actually changing it?

[DomR]

I see people doing this all the time. They change their photo to a new one, then 3 days later they'll 'change' it again EVEN THOUGH it is the exact same photo with the exact same number of likes however it is not a re upload you get me? I don't understand because it's not me reading the same post again because it says 25 mins ago.
Example, Thursday new profile pic. Saturday 'changed' profile pic. Both are the exact same exc te fact that the latest one has more likes. How do you do this?
Also, how do you 'select' a different profile picture that has been your profile pic before without having to upload it again?

[melissa]

They go to the image they originally had as their profile picture and then set it as their profile picture again. People do it to get more likes without having to properly change their profile picture.