How am I supposed to position my link monster?
What am I missing?


Perhaps you are missing that the Game Field recently changed, with the creation of Link Monsters.

Now, monsters from the Extra Deck are to be placed on the Extra Monster Zone.  These are two new zones "shared" by both players.

The rules now say that you may only play an Extra Deck Monster (Synchro, Link, XYZ, Fusion) on such new zones, or well on a regular Monster Zone if any Link monster's arrows point to that Monster Zone. In other words, placing Link Monsters enable you to place more Extra Deck monsters on the Zones they point to.

Be aware that if the arrow happens to point to an opponent's Monster Zone, then they are able to place Extra Deck monsters there also. As in the case of your Decode Talker, we can see it has 3 arrows, and one points straight, towards one of your opponent's Zones. This enables your opponent to place Extra Deck monsters there as well as in the other ExtraDeck Zone. 

This in some way "balances" the power of Decode Talker; given it is a card that gives you great advantages, enabling your opponent to do this sort of evens things out. Furthermore, almost all Link Monsters that have some powerful effect point to your opponent's Zones, as to balance the power of their effects (contrary to the less powerful Links, as they don't usually have arrows towards your opponent).

This is the reason why your Decode Talker has such arrows: it enables you 2 new zones to play Extra Deck Monsters, as well as one for your opponent. It is important to stress that where you place your monsters in this new field is an important part of any game strategy. Before this changes little mattered where you placed your monsters, as long as you had space to play them there were virtually no advantages of placing a monster on a specific Zone.1

1One exception that comes to mind is Alien Infiltrator. This interesting monster takes advantage of its position (and can even move!), as it reads:


  Once per turn, this card can move to an adjacent (horizontal) unoccupied Monster Card Zone. If no Spell, Trap or Monster Card on your opponent's side of the field is in the same column as this card, it can attack your opponent directly


As you can see this was an unusual card back then, but now placement of monsters is more relevant to any strategy as compared to before.