Duplicate supplies often start with one small shortcut
The household is busy. Someone cannot find the open bottle, tube, roll, or box. A new one is nearby, so they open it.
Later, the first one appears.
Now there are two open items, both half-used, and neither feels urgent to finish.
This happens with cleaners, shampoo, toothpaste, paper goods, pantry supplies, bags, wipes, and many other household consumables.
The problem is not only buying too much. It is opening too early.
Name the active item
Every category needs one active item.
That means one item is currently being used before a backup gets opened.