Killed by the unions like so many other good papers.
Ummm ... not according to anything I know. The Bulletin was done in by the TV - it was an evening paper, so the news was stale by the time people got it. Circulation dropped, and the paper lost money.
Read up on it here.
You might note the Unions gave $4.9 million in concessions (quite a lot more in monetary terms 25 years ago) in the midst of the huge 1979-1982 recession.
Its a sad thing, because it was definitely the better paper - and it was a real paper that told you everything you needed to know. The Inquirer has been an internationalist liberal screed for quite some time - ever since Annenberg bought it from Col. Elverson.