Don't retroactively paywall articles.

Don't retroactively paywall articles. If something was published free, it should remain free. Unfortunately, many websites continue to charge for content that was previously free to access. The Verge, for example, occasionally displays paywalls on decade-old articles that previously had none.

Poor Implementation

These paywalls often only appear when the user starts scrolling. They tease you with part of the article before asking for money, instead of outright saying you need to pay for this.

When I see paywalls implemented this way, my perception of the site lowers immediately.

It says to me: We aren't reliable. You can't trust us to keep this content available in the way it was once published. Sure, availability was never guaranteed, but it is diminished with the decision to paywall free content.

Paywall Circumvention

It can be argued that paywalls help fund content availability in the long run. After all, serving webpages continuously costs money. Generally, paywalls aren't the problem. However, I believe that retroactive paywalling of otherwise free content damages the trust users place in your site. It's a belated monetization strategy that weakens your site's appeal to paying users.

A further, proven consequence of this is paywall circumvention. Users that aren't willing (or able) to pay for these pages will flock to services like archive.today and archive.org to find pre-paywall copies of pages, bypassing your live page entirely. Alternatively, they might simply find a competitor's free-to-access page and engage with similar content there instead.

A Better Way

Personally, I find it more transparent of a website to tell me directly that a page is behind a paywall. Of course, if I'm expecting to read a free article, I'll still leave upon seeing a paywall. No hard feelings. However, people who are more willing to pay will likely stick around to read the teaser even after they're told there's a cost.

In either case, the user is quickly informed and their time is respected. You retain the paying users and reduce the disappointment for others.

Ultimately, many people have been conditioned to expect free content from a webpage. Naturally, then, the shift to an increasingly paywalled web is an uncomfortable one. Webpages aren't movie trailers. A movie trailer is automatically understood as 'not the full product.' As a user, however, when I click a link, I expect the 'feature film,' and yes, for free.