Why are relevant ads important?
Ads are a critical part of a good search experience. For example, a search user looking for "hotel deals" is likely to encounter ad results that are as relevant, if not more relevant, than organic search results. By providing the best product for our search users, we also create more conversion opportunities for advertisers.

How relevance is measured
Microsoft Advertising adCenter provides Quality Scores to help you understand how competitive your ads are in the marketplace. If a keyword has a Poor Quality Score, it means the keyword has a limited eligibility of being served; you can improve the score by changing certain elements of your ads and landing pages.
Use your Quality Scores to determine where there’s room for improvement so you can get the most for your advertising spend. You can view aggregate Quality Score data by time frame in your Ad Group and Campaign Performance reports. You can also view historical keyword Quality Score data by any given date in the Keyword Performance report.
Improve your relevance
See these talking points for helping advertisers overcome different QBR classifications.
Keywords should be closely related to the advertised product or service.
Example:
Northwind Traders sells home appliances. Their ad for dishwashers and other appliances appeared when the user searched for "patio umbrellas." Their ad is not relevant to the user's query.
Why:
Northwind bid on "patio," resulting in their ad showing. Because their products are not used for patios, this keyword is inappropriate for their ad.
What to do:
Remove the irrelevant keyword, "patio," and add relevant ones to ensure the ad appears when users are searching on topics related to home appliances.
Ad titles, text, or display URLs should be related to the bidded keywords and to the advertised product or service. Also, strive for grammatically correct ads: no typos, misspellings, or any text that doesn't make sense.
Example:
Wide World Importers promotes merchandise imported from all over the world. They correctly bid on watches and their ad appears. However, the ad copy reads -- "Great a watch from Bargains," which is not grammatically correct.
Why:
World Wide Importers use dynamic keyword insertion, which led to unintended ad text.
What to do:
Correct the ad copy to get a higher ad position and/or lower CPCs.
The user experience on the advertiser's landing page should be positive and compliant with all adCenter policies. Advertiser sites with a poor user experience reflect badly on the search engine and on high-quality advertisers who advertise with us. Misleading content, controls that don't do what the user expects (such as a close button that actually launches a new page), and other experiences that trap or trick the user will cause an ad to be ranked very low.
Example:
Graphic Design Institute's site provides a poor user experience. It includes what looks like a Slide Share about graphic design, but clicking on it actually takes the user to a page to sign up for online classes. Furthermore, that page has no close button, making it hard to exit.
Why:
Graphic Design Institute is using misleading tactics on its website.
What to do:
Strive for the best possible user experience and avoid using misleading tactics.
Landing pages should have relevant, original content that is consistent with the ad.
Example:
World Wide Importers has an ad for furniture that correctly appears when the user submits a search query for "furniture." However, the ad takes the user to a list of wholesale furniture ads. The user expected to go directly to a retailer's page, not to another list of search results.
Why:
The advertiser's landing page is essentially a search results page with no original content.
What to do:
World Wide Importers needs to provide original content on the landing page to make it more valuable for the user.