I teach beginning readers, and the best guess I have is, they're sight words (high frequency words that don't follow phonetic rules - you just have to recognize them on sight).

That being said, I don't know what good just having these words around will do. Sure, you have to be able to recognize them, but there's no context if they're just randomly on stairs.

I can't even guess what was being attempted here.

You Want Good? To Me It, Am Come Where? What The Said! 💀