Google managed to sell just 20,000 units in the first week of sales, and now reports from Flurry are suggesting Google only sold 80,000 units in the first month.

Google’s poor sales could be the end result of poor advertising with a small budget compared to the iPhone and Droid.  The Google Nexus One is also limited to T-Mobile, but does come unlocked, if purchase through Google’s website.

As compared to first month sales of the iPhone (about 600,000) and the Droid (about 525,000), sales of the Nexus One do appear to be moving along rather slowly. A lot of factors probably contribute to the relatively low numbers, key among them the lack of traditional marketing expenditure (as compared to, say, the $100 million ad campaign for the Droid) and Google’s direct-to-consumer sales approach, which, although innovative, is simply not something the typical mobile consumer is used to.