The ‘real’ value of a high (or in this case – low) Alexa ranking has been an interesting topic of debate for quite a few years.
First off lets tell you a little bit about Alexa and what they are all about:
Alexa computes traffic rankings by analyzing the Web usage of millions of Alexa Toolbar users and data obtained from other, diverse traffic data sources. The information is sorted, sifted, anonymized, counted, and computed, until, finally, we get the traffic rankings shown in the Alexa service. The process is relatively complex…
One of the major flaws in this system and the reason Alexa has received a lot of negative feedback is because testing has shown that the usage stats from its toolbar installations is the primary source of the data used for ranking. This in itself is not a real problem because that is the easiest and most in-depth way for them to obtain ranking data. But time-and-again experiments have shown that webmaster type sites will have lower Alexa ranking simply because your average Alexa toolbar installation is done by webmasters and those type of savvy internet users that visit webmaster related sites frequently.
I myself have owned many web directories over the past 4 years and have always noticed it is very easy to get a low Alexa ranking on those sites when compared to my other topic sites.
A second problem that has arisen is shady web marketers that purchase traffic in order to pump up their Alexa results to make a site appear more successful than it really is. Alexa reports the traffic volume as accurately as they can but they don’t have the capability to report the quality. Because of this the system is open to abuse.
In conclusion, Alexa is far from perfect and should not be used as abosulte proof of traffic but it is ok as a loose guideline. If you are considering making a website purchase and traffic is a part of the price you should definately ask for acccess to the owners third-party traffic program, like statscounter or simply ask for the backend stats from the host, awstats is good for that.