Pointing varieties

Does anyone know why and how this happens, Im assuming it isn't an error and that these varieties actually have some reason in the manufacturing process.  

Do you mean things like arrows up, arrows down (like on Spanish coins)?

 Maybe the lettering pointing either to a bead in the border, or between beads.
If so, then perhaps the die to press the coins is made up of different parts, and the beading got turned. Or redesigned. Example below, where the smaller 10 pence UK coin has the letter I of ELIZABETH on the top coin pointing to a bead, whereas it is between beads on the lower coin, in the same 1992 year.

                               

Its as Zac says with part of a letter or number faces a border bead or between them and can even pointing at the bead but a little to its left or right. I did read about them some time ago but cant think of the reason why its done, it is a deliberate thing Im sure but i just cant remember why.