I recently invested in a decorative trivet to keep on my kitchen table at all times. I had never seen the need for one because I usually keep all of my hot pots right on the stove. Usually I don't even use serving dishes on the table -- I just dish up the food right out of the pot.
But I recently cooked a frozen meal in the microwave, took it out, and set it on the table. It ended up damaging the surface of the table, and I might have to have it refinished.
Now I keep the eye pleasing trivet on the table at all times, so it's there even when I don't expect to need it. I didn't think something I cooked in the microwave could damage my table, but I learned my lesson.