Ads are the only part of a PPC account that a searcher ever sees. All your other settings and targets just tell a search engine if your ad should be displayed or not to a searcher. In the end, ads are one of the most important aspects of an entire PPC account. Testing ads can increase your conversions, lower your cost per conversion, increase your quality score, and offer many other benefits across your account. However, most ad testing is not done correctly.