Half of the Money Spent on SEO is Wasted
Offline advertisers have a saying that half of the money they spend on advertising is wasted -- they just don't know which half. Solving that sort of problem is what search engine marketers (both paid and organic) have been able to do with the proper implementation of web analytics. The PPC folks are the best as they are able to calculate a cost per click or conversion and they're able to point to what modifications in their campaigns resulted in a change in results. The SEO side of the house used to be able to come close to the reporting accuracy of paid search, but recently connecting activities to results has become nearly impossible.
Before you go off screaming how half-baked my statement is, let me expand on it a bit. First off, SEO in this context is ANYTHING that results in improved organic search visibility and traffic. The list includes not just the usual on-site stuff, but also social bookmarking, community outreach, content distribution, digital asset optimization, and local search. The problem with having so many avenues to approach the SEO problem is that it has become next to impossible to attribute an uptick in organic search traffic to any one activity. The situation is exacerbated by the reality that multiple activities will be happening in parallel which further confounds the attribution problem.
Now I'm not saying that an experienced SEO is just going to throw everything at the wall to see what sticks. Far from it. A good SEO will assess the problem, work on a strategy, and select from the set of all known SEO tactics to formulate an approach to achieve the strategy. And that SEO is undoubtedly confident that as a set of tactics, the chances of success are very good. At the same time there is the knowledge that some portion of the tactics chosen, even if executed well, will not have a noticeable impact.
A Bit of Fiction
Here's an example of how things might play out. In Jan 2010 I finish writing a new ebook on SEO (I cleverly call it The SEO Book). Now being an SEO Expert according to SEOmoz, I proceed with a plethora of optimization tactics. For 2 or 3 months I see improvements and I manage to get to the first page of the Google SERPs for "seo book". Some other dude has the number one spot.
In March, when the snow in NY is gone, I happen to meet up with Mike Grehan of Incisive Media for a couple of drinks (hi Mike, I owe you a pint err.. maybe a keg by now). Amongst other topics I mention my new SEO book. Mike, wanting to help me says he'll put a tweet out with a link to my site. Great!
The next day, unbeknownst to me, Mike realizes that he won't actually have time to read my book and being a man of integrity doesn't want to promote it without actually having read it. Still wanting to help, he mentions the book to a few folks at ClickZ. Nothing happens until a month later when one of the ClickZ authors has a severe case of writer's block and decides to check out this book I've written. He loves it and publishes an article about it. He uses the clever title, Marios Alexandrou Might as Well Be Called Aaron Wall 2.0 (an SEO can dream, right?). The article inspires some links and mentions for a few days and a month or two later my site is up above the fold in the SERPs. Awesome!
So, should I have bothered with SEO for the first few months or was that money wasted? Would the results from the ClickZ article have had as significant impact if I wasn't already on the first page of results? I can't say. The only thing I can say is that in such a scenario, I wouldn't have changed a thing since in the end from January to May the return on my efforts exceeded the cost of those efforts (even including the keg for Mike).
So ultimately, it may not matter that some of the tactics failed as long as the overall results produce a positive return on the SEO investment. But, that does bring me back to my point that some portion (and I wouldn't be surprised if it was half) of SEO budgets are wasted. Or to put it another way, the same results could be achieved with half the money.
OK. Now you can go off screaming.