Before Search Engine Optimization (SEO) and Search Engine Marketing (SEM) can be explained in the context of which is more effective let’s start with a definition.
Rospigliosi (2013) explained the terms by:
Search Engine Optimization (SEO) Definition
The results found through organic searches relating to the word/phrase that was searched. For example, for Google the results shown will be presented by showing websites with the relevant keywords, how recent the website was updated and how well the site is sourced by other websites. But as Schwartz (2014) explained Google’s exact formula is a secret as they do not want organisations manipulating the results.
Search Engine Marketing (SEM) Definition
These are the paid for results. This means they are selected by the search engine automatically depending on what you was searched. They are often localised to your current location. Google’s version of these are called AdWords.
So Which Is Better?
The answer is… it depends.
Khurana (2013) states that for short term fast ROI, SEM is the better way to go as results are gained quickly while costs and revenue gained can be monitored easily through tools such as Google Analytics. SEM results are also good for time sensitive offers or a new website that has yet to develop effective SEO results, Kim (2010). Khurana believes that ECommerce websites typically have poor SEO results mainly due to fierce competition so SEM can help overcome this. However keeping this strategy long term could be very expensive.
Although increasing page ranking through SEO can take time once it is done in the long term it usually is the most effective at brining in more customers, (Khurana, 2013). Khurana also states that users often try to avoid SEM results as they find the SEO results more credible. However Kumar (2012) explains that page ranking systems change, so SEO techniques need to be constantly adapted which can be expensive if the company has to outsource this work.
In conclusion both methods have their advantages and disadvantages and many companies use both. Kim (2010) states that sometimes companies use both just for SERPS dominance. In the end it should be remembered that both tools are essentially trying to do the same thing, drive traffic towards your website so both need to be at least considered if budgets allow.