It's been a long standing fact of how the inventory works, really. Pretty sure not an intended feature, though :p
Yes, when dragging items from your inventory to the game world, there seems to be a delay between when the first click to pick the item happens and when it registers the first click, which could happen to be when your cursor is over a completely different item by that time.
I'd assume it's something that Larian are looking into, but I don't know what actually causes this kind of input lag.
