Many newspapers and content producers who have migrated part of their business to the web have regularly flirted with the idea of pay walls. As a whole, the industry has not jumped into it because it gives competitors an edge to steal their readership during the transition time. Also, it is unclear whether pay walls will work for the industry. The effects of a pay wall system can often emerge long after one might expect. What is clear is that the internet will be a dominant force (medium) in the news industry, and content producers are desperately seeking out new and better ways to monetize their product.
Salon in 2001 was a pioneer in the pay wall system with their Premium programme. In a recent article "Memories of a paywall pioneer" by Scott Rosenberg, former managing editor of US website Salon.com, the effects of setting up such a system are examined in context of today's market.
(Source: https://www.guardian.co.uk/media/2009/dec/03/memories-paywall-pioneer)
Specialized information or niche content tends to fare better than more widely publicized content in the pay wall system. Obviously free alternative can kill the pay wall option.
"But the value of stuff online is usually tied to how deeply it is woven into the network. So locking your stuff away in order to charge for it means that you are usually making it less valuable at the moment that you are asking people to pay for it. And that's why people so often respond with: "No thanks."" Source: Scott Rosenberg, "Memories of a paywall pioneer", Site URL: https://www.guardian.co.uk/, Thursday 3 December 2009. Mr. Rosenberg describes the one of the challenges of a pay wall system is to not confuse readers about how they can access content--as it can lead to a loss of readership that takes time to build back up again. Salon faced this problem when they experimented with a day pass approach--which allowed readers to have a free access pass for one day if they watched a 30-second video ad.