In the 1960s when the first crosslinked polyethylene (XLPE) insulated medium voltage (MV) cables were installed, industry expected them to perform reliably for 20-30 years.
History shows that the service life of some of these early cables failed after only 10-15 years due to defects from voltage stress, moisture and other imperfections within the cable structure. It has been estimated that for every dollar that utilities spent installing cable, they had to spend at least 10 dollars to replace it, with some still dealing with this today.