I don't know how it works here, but where I used to live if you got a lien on your property you weren't necessarily notified, and then they charged you interest on the lien forever, and gave you a large bill and then would take your house from you.  So...while yeah, we should all be up on all of that (and I found out about the $150 I owed because we sold our house not long after I hadn't paid the garbage bill...long story...) -- sometimes we don't know what is happening because we don't get the information because someone will benefit from it.