You are making your breakfast, toast and butter, and you realize you need a knife so you go to the other side of the kitchen to get it.  On the way you forget why you are walking.  So you walk back to the toaster and, looking at the toast, you suddenly you remember you need a knife.  So you head back to the flatware drawer and realize you also need a plate so you grab a plate and head back to the toaster where you remember you forgot to get the knife.

You walk back to the flatware drawer and promptly forget why you are there.  So you walk back to the toaster and see that the toast has popped up.  Looking at the toast for a minute (or an hour), you realize you forgot to get the knife so you walk back to the drawer.  On the way you pass the refrigerator and realize that you also need the butter.  So you grab the butter and head back to the toaster where you remember that you forgot the knife.  Walking back to the drawer, you forget why you are there.

You head back to the toaster as this is the only thing you can now remember.  When you get there, you realize that you can’t eat your toast without the butter and you need knife to spread the butter so you head back to the flatware drawer to get the knife when you pass the clock. It reads 12 noon so, now that it’s lunchtime, you’d rather have a sandwich.

At this point, you’re too tired to make it so you just sit down and that is why you find petrified toast in the toaster and melted butter on the counter at dinner!