Always focus on conversions and ROI with your marketing..
ROI is the ratio of your costs to your profits. With Google AdWords, the higher your quality score, the lower your Cost Per Click and Cost Per Conversion.
To improve your ROI with all PPC campaigns, you first need to start measuring conversions. Once you've accomplished that, you can evaluate your ROI to make sure that the dollars you spend on advertising are turning into profits for your business.
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