Do flat irons need to be replaced?

I’m wondering if flat irons (hair straightening) need to be replaced after a long period of time. I have a good quality flat iron that was expensive but I got it about 5 years ago. Though it still works well (I think), I am wondering if it is damaging my hair or if getting a replacement would be better for both my hair and for the ease of straightening?
any comments or suggestions would be helpful
thanks!