NJ Tax Certificate question

[Maximo Cortese]

I have been recenelty reachering a lot about Tax Certificates in NJ and came across a speedbump i cant figure out. I have noticed some investors buy a TC hold it for a while then file a lis pendens to foreclose (2 years after). Sometimes I see another Tax Certificates Sale (by another entity) shortly after the Lis Pendes is filed (by the first TC holder). 

Is that because the original TC holder gave up paying the subsequent taxes, thus a new TC went up for auction?