The basics of advertising on Google AdWords are the following:

1. Create a Campaign
2. Create AdGroups within the Campaign
3. Add Keywords to AdGroups
4. Add Ads to AdGroups

When you first post your ad Google AdWords will calculate an initial Quality Score (QS).  But that’s not the end…  Your QS will change over time.  In fact their support told me at one point that an ad’s QS changes with each user click.

Quality Score Factors

AdGroups and Keywords

When you add your ads to your AdGroup you create a unique ad for keyword.  However, Google appears to assume that the more keywords there are per AdGroup the more generic the ad copy will likely be.  And there’s good reason to assume that.

As a result most PPC experts suggest one keyword per AdGroup to improve you Quality Score (QS).  There are tools to help make that easier and faster.

Ad Copy

Ad copy is the most obvious Quality Score factor.  Google likes to see the keyword in the ad.  The more often the better.

Landing Page

In September 2008, Google AdWords changed the Quality Score calculation to include the Landing Page (LP).  The relevance of the LP to the keyword is a factor when determining the QS of your ad.

URL

Google considers it a sign of keyword relevance if the keyword is in the display URL.  (Destination URLs may also be important, I’m not sure.  Many times the destination URL will go through a 3^rd party tracking site and then a redirect to your page.  The final pages the user ends up at must be the display URL so I assume that the destination URL is not a big factor.)

Domain & Account History

When I was first learning how to advertise on Google I ran a lot of bad ads for CPA offers.  A natural consequence of running CPA ads is that you run ads for a lot of domains.  As I learned how to write better ads I found that the original domain that I attempted to advertise on could no longer achieve a high initial Quality Score.  The initial QS remained high no matter what I did so advertising for that domain became too expensive to ever be profitable.

During my learning phase, it became clear that no matter what ad I wrote and no matter what domain I pointed it to that Google wasn’t going to run my ads.  Google’s terms state that you can’t have more than one account but they had effectively killed my first account.  No matter what I paid I couldn’t get my ads to run and I certainly couldn’t be profitable.  So I created another account and copied the ads from the bad account.  The very same ads ran well (and cheap) on the new account.

Performance (CTR) & Competition

If you advertise on a keyword with little competition Google is more forgiving when it adjusts your Quality Score over time.  However, in general your QS over time will be dependent on your Click-Through-Rate (CTR) vs. your competition’s CTR.