Do you really know what you need?

We recently let friends stay at our place while we were out of town. It took a three-page single-spaced set of instructions to give them an overview of our place. And after their visit, I have the sinking feeling that there are still too many things I failed to mention—doesn’t everyone’s pipes sometimes rattle? Should I have said the fridge needs to have its door jiggled? This puts to mind that we really, often don’t know ourselves as well as we might. If we don’t know our homes, how well do we actually know our businesses?