Collectability of Delinquent Property Taxes

I was doing some research for my thesis and came across this article from 2015 which talks about the difficulties in collecting delinquent property taxes. It raises an interesting question about the priorities of the City of Philadelphia when it comes to different initiatives and agenda items. The City prioritizes collecting these delinquent taxes over putting a site back into use; however, when it comes to blighted and abandoned properties it is unlikely that the City would be able to easily collect these taxes (e.g. because of absentee property owners).