In other words, the object of patent protection can be either a method or a product.
For example, if you invent a new cup, it is a new product and you can apply for patent protection.
You can also invent a new manufacturing method for existing cups. Maybe the new method makes the cup stronger or more productive, so this method can also be protected.
Of course, these two situations are different, so the law should be very strict to include both situations.
If the law only protects the method patent and does not protect the "products made by this manufacturing method", then the products on the market can not be processed, and it is difficult to protect them in essence.
If you say goodbye to patent infringement, it is difficult to prove it. (Unless you can sneak into his factory and film all his manufacturing processes, hehe)