The warranty/guarantee is different from the average lifetime of the device, which is defined in the law as the average period a device must maintain its working parameters stated by the manufacturer.

In some countries a fridge is expected to have a lifetime of 10 years but a warranty of 2 years. So in theory if you could prove that the fridge cannot meet the expected average lifetime, the cooling ability decreases below the stated parameters much earlier, then it becomes the manufacturer’s responsibility.