Whether its a movie star that is known for his action films (and struggles whenever cast in a romantic comedy), a pop star that is known for dance music (and struggles to make a country album), car company known for sedans (who struggles when they release a sports car), the list goes on and on. Think about that favorite song you love - it's usually one brief segment that you identify with it. In music parlance, that's the "hook" and its what matters the most.
In the market place, once your known for your "thing", moving into something else is really hard. It actually is probably harder than just starting anew. It's so hard that for those that do succeed, they are usually given a new label ("renaissance man", "slash", etc.). At Topix we learned this when we started out as a news aggregator. We were successful, which is great. But now the site is really a thriving community site. So why do most folks still identify us as a news aggregator? The power of one.
Marketers have known that for years, and have spent lots of blood, sweat and tears trying to come up with that one thing that they can wrap their brand around. The quicker picker upper. Tastes great, less filling (pretty clever, huh? Two things merged into one). Driving (BMW) and luxury (Mercedes). Trying harder (Avis) and convenience (Hertz). Multidimensional products defined in singular terms.
Unfortunately, lots of online start-ups have forgotten these lessons. Why? One word: SEO. In the Google regulated world fo the internet, if you launch a bunch of content/ information under static URL's and optimize those URL's to various keywords, you can actually catch a fair amount of traffic. This SEO traffic is so easy and appealing, the natural reaction is "where do I get more?" The answer of course is optimizing more content, but for a completely different set of queries.
As a result you have people launching many, many pages of of data that is wholly unrelated in the consumers mind. This goes completely against the power of one. So yes, they get their additional traffic, but it is at a cost.
These sites that spam the search engine may provide content for a variety of queries but completely fail in sticking in the consumers mind as a destination site. What's the difference you say? Well, many things. Selling ads to people for a site they never heard of, regardless of traffic numbers, is, um challenging. So you get stuck with the networks. Also, when you live by the SEO sword, you can easily die by the SEO sword. Just ask the price comparison engines. And finally, other than a few chosen sites, the SEO traffic you receive caps out well short of that needed to grab a piece of the consumers mindshare. But I've already said my piece there.