This is an incorrect analysis.
The manufacturers duty is to properly design, test, manufacture and instruct the user as to installation and use of their products.
The manufacturer knows or should know the useful life of its products. A $15 hair dryer, coffee maker, and other consumer products may not last forever. On the other hand, if they wear out they should just stop working. They should not cause a fire or water damage.
The manufacturer must instruct the user to inspect the product and notice particular things indicating imminent failure, such as cracked hoses, cracked wires, and the like. Otherwise, how is the user to know the product will fail and cause damage?
Some states, like California, have no statute of repose for product defects, and we have made subrogation recoveries on products as old as 35 years. Other states, like Oregon, have a statute of repose after which suit may not be filed, generally commencing from the date of purchase. Be sure to check the statute in each state!
If a product wears out, what caused it to wear out?
Ask your expert to identify the manner of wearing out (cracking, splitting, chemically embrittled, etc.) What compound caused the corrosion? What caused the cracking?
These may be signs of an improperly designed product.
If the product wore out due to coming in contact with a compound, such as chlorine or cleaner, did the manufacturer warn the user not to use such compounds? If not, there may be a good case of product liability for failure to test and failure to warn.