Once in a while the genealogist needs to remind themselves that there might not be an answer to a question. This does not mean that one does not keep looking, but that sometimes there just are not the records available to answer the question, determine the parentage, connection etc. Sometimes knowing when you have exhausted all avenues is a good thing to know. Of course, it also might be advised to ask an expert if you really are at the end of your genealogy rope.
A certain publication made me take similarly worded paragraph out of an article because it was "too negative." I think it's realistic and honest which is a much better way to be.