Some of us have learned this lesson the hard way. If you don't clean your curling irons and flat irons, they get ruined. That is because the hair products we use to style our hair can hurt our irons. Below is a a flat iron that I got lazy with and didn't clean. The products I used baked onto the plates. I didn't clean the build up off of the iron. With time, the baked-on residue deteriorates the ceramic coating. The coating chips off and now you are putting your hair directly onto the heating plates. And that fries your hair no matter what products are in it. Long story short, you have to clean the iron.
First, if your iron is in really bad shape and you are hoping to save it, you could try the product above in the pink spray bottle. This is Dissolve All-Purpose Extra Strength Styling Iron Cleaner. Basically, this is a cleaner that you can buy from Sally Beauty Supply that is meant to clean off the build up. You spray it on your iron, let it sit for 30 seconds, then magically wipe your iron clean with a paper towel. Personally, I own this and have tried it. If your iron is already dirty, I find this doesn't do a whole lot, but it does help.
Second, if you don't feel like shelling out the $5 - $7 for Dissolve, there are a few household items you can use to clean your irons. You can use rubbing alcohol or nail polish remover. Put some on a cotton ball and rub over your iron. I find this works just as well as the Dissolve and you probably already have it at home.
Third, and most effective in my opinion, is to prevent the build up from ever happening. You really need to clean your iron every day to prevent the build up. Also, this is really easy to do and free. After straightening or curling your hair, allow your iron to cool until it is lukewarm to the touch. (You don't want to burn your hands!) Then dampen an old towel or paper towel and simply wipe away any residue. Free, easy, and keeps your iron in great condition!