The "Under Construction Sign" is a very strong symbol of the early web. It reminds us of the great times shortly after the scientists and engineers finished their work on the Information Highway. Ordinary people came with their tools and used the chance to build their own roads and junctions. Work was everywhere and everywhere there was something that wasn't ready, links were leading to nowhere or to pages that didn't quite exist and there were signs on the pages that warned of broken connections and the lack of navigation.
Step by step people were developing pages into a functioning web and it became less necessary to warn us, especially using road signs, about missing information. But they didn't disappear. Instead, "Under Construction" images changed their meaning from a warning to a promise that this page will grow. The symbol became a hybrid of excuse and invitation. It could appear on an empty or properly functional site as a sign that the project was growing and being updated. Often you could see the newer sign, "Always Under Construction."
"Always Under Construction" didn't mean the site would never work but actually the opposite. It informed users that there was somebody who was always taking care of the site so it would be interesting to return again and again.
This was a very important message because it was crucial to really insist on the idea of constant development and change but the sign was wrong. The association with broken roads and obstacles on the way didn't illustrate the idea of ongoing development. Around 1997 the sign turned into a meaningless footer and became a common joke. Even the mainstream press wrote that the web was always under construction so, after a while, people stopped putting it everywhere.
Neither the "Under Construction" sign nor the idea of permanent construction made it into the professional web. The idea of unfinished business contradicts the traditional concept of professional designer-client relations: fixed terms and finished products.
There was some follow-up though. The phrase, "This site is currently undergoing redesign" became an elegant substitute for blinking road lamps. New ways to show the project was constantly updated appeared as well: current news on the first page, a "Last Updated" notice, or the ridiculous -- but still very popular -- solution that creates a magical effect of actuality and telepresence: put a clock on the web site showing the current time.
So what's with the very idea of web construction? Is it still around and how does it show itself today? I'd say yes. The "Under Construction" signs have unexpected followers, the "Verified XHTML" buttons. You can see them on more and more pages of modern web users.
They are there, (to quote the W3 Consortium), "To show your readers that you have taken the care to create an inter-operable Web page." In other words, the new sign says the developers of the sites are taking care to reconstruct the web to meet new standards and to bring the "world's biggest trash pile" into a faultless, clean and clear code environment.
I'm not a fan of this development but I do like the appearance of the XHTML buttons. They manifest the power of end developers and show the great intention of participating in the global construction or reconstruction of the whole environment simply by making your own site.