Writing in this blog last year, Matt Paines talked about the need for one's online marketing strategy to be more conversion focused (quality based) rather than traffic focused (quantity based).
When you're paying per visitor, you want that investment to pay off as much as possible. So how can we do this? A search query is a type of question and your campaign should be set up in a way that would present your products or services as a viable answer to that question. There are three elements to this: keyword targeting, ad copy and the landing page. Choosing the right keywords ensures your campaign will attempt to answer only those questions that are suitable to what your company wants to provide, the ad copy will tell the searcher that the answer he/she seeks is likely to be found on your website and the landing page will (hopefully) provide that answer. As I have touched on in my previous post about internal SEO, the weakest link in the pay per click chain is more often than not the landing page.
Believe it or not, getting people to visit a site is not difficult. If I put an ad up saying all visitors to my site will get free money, I would undoubtedly get plenty of visitors. If it then turned out that there is no free money at all, but I am actually trying to sell them something, those visitors would likely be very angry and not particularly interested in what I have to offer: I would effectively be making a promise I can't keep. This may be an extreme example, but many pay per click campaigns do exactly that - they target a keyword, they make promises via their ad copy to answer the searchers' question, but then deliver a landing page that fails to provide the desired answer. Unlike my example, though, the problem is more often than not bad presentation rather than the inability to provide a service.
When presented with a landing page, the searcher will probably spend a miniscule amount of time assessing whether this is really what he/she is looking for, maybe even a second or less. Anything that doesn't instantly scream "result!" will mean a hit of the back button and loss of money for you.
Here are some common problems I have seen with landing pages. The list is by no means definitive: