There are international versions of Time and Newsweek . Audience targetting, and demassification . Mass magazines were hurt by TV in the 50s and 60's and some went out of business like SEP , Life and Look . Now there is a narrower focus, and targetting of audiences and homogeniety of magazines, although the industry itself is heterogeneous. Challenges to industry - competition and imitators, and a limited economic base.
Magazines come and go a lot, and newer tv channels are competing a lot.
More ad pages irritate readers, special deals for subscribers. Cross-media discounts when a company owns more than one medium. Web-based magazines such as Salon are taking away readers and ad dollars.