My rowenta is over six years old, my cord cracked near the plug area (cracked within the first year), and my husband replaced it with a heavy duty plug replacement. He told me it was from me pulling the cord to remove it from the outlet rather than using the plug. (Yep, I am one of those people - if I am an a hurry, I yank, rather than unplug).
I try not to do it any longer.