A manufacturer’s responsibility generally includes foreseeing reasonable modifications and misuses of their product by consumers and providing suitable warnings for those. If an alteration is highly unforeseeable or beyond the scope of normal product use, the liability might not be as clear-cut.
For example: If a lawnmower is repurposed into a snowblower and the manufacturer had not indicated such a use is dangerous, they might not be held liable if this use was not reasonably foreseeable.