Exactly. I learned that the hard way in the fall with the incredible non-stick walls (as in, the plaster was coming OFF the concrete walls). We eventually found the proper patching material after a few days of wrestling with it (same brand, different product), so if it ever happens again, I can fix things properly. That's also why I ponied up $3k for a new shower from Bathfitters rather than do a crappy $500 fix. I hated spending that amount of money, but it was VERY worth it.