Google has announced that from the week starting 12 September 2016, you’ll start seeing null Quality Scores (designated by “—“ in the table) when there aren’t enough impressions or clicks to accurately determine a keyword’s Quality Score.
“A result of "–" will appear for new keywords, as well as keywords that lack recent click and impression data. By default, Quality Scores of "–" won’t be included when filtering by Quality Score in your reports or automated rules. But you will have the option of including Quality Scores of “–” in your filtered data.”
Rather than defaulting to a reported score of 6/10 (which Google rolled out in July 2015) a score will only be given once enough impressions or clicks accumulate.
Google hasn’t shared whether or not this change is going to impact ad rank calculations or ad serving.
What we know is that the main change we’ll see on the front end (what we see in our accounts) is brand new keywords will no longer automatically get assigned a score of 6. Once the keyword gains enough impressions, a score will be assigned.
For account managers, it means you no longer have to panic unnecessarily when your new keywords have a low Quality Score with very few impressions.
This will also benefit those who like to keep tabs on their estimated Account-Level Quality Scores and curse those low-impression, low Quality Score keywords from ruining your entire day.
For more background on quality score and how it works, check out this link to Google’s About Quality Score article.