Why is there a constant trend of nerfing turrets each season.

Early season 5 Inhib turrets were good not amazing but decent, they still dealt the same "meh" damage but they actually had utility with a slow and armor reduction. Then the only thing people were asking for is for turrets to deal damage past 5 minutes. Now that inhib turrets have been nerfed with nothing to show but a crap laser, shielding on the tier 2 mid turret removed and in this preseason turret resistances a complete joke why even bother. You cant reliably defend them from splitters/turret shredders, leave it alone for another objective such as catching someone or getting drag/baron and it will leave you with a destroyed lane/base. We just want turrets to actually be what they are called. They are made of stone and should not be shredable until at least 30 minutes into the game . As well as giving them either more utility or damage because what they have right now is a joke and they have been a joke. With snowballing at an all time high its horrible to see your turrets explode so easily. Leaving you in your base to simply lose as super minions flood your base and the enemies simply win or get all the farm and vision denial they need to win.