Yes that is true, I have read many articles that there are some projects are dead. I also experienced that status, because my wife also join other bounty , after for how many months they are in the projects. there projects was dead, it does not met the standard. So, they did not earn any single amount for that bounty period.
It was told somewhere on the forum, that almost 40-50 project appear daily. That is quite a lot, and it is not surprising that they are closing. I think that it is not the big problem