Do Not Change Keywords Too Often
Allow at least six months before you take action to choose different keywords. Keyword success depends heavily on other factors. For example, it is possible that you have the right keywords in your title and meta, but the audience that is getting the results might not be the best one to convert. There could also be a market recession related to your niche, and although you are getting traffic, conversion might not be enough. However, this doesn't mean your keywords are not good, but rather it is just a temporary glitch. Be patient.
Using Analytics and Live Monitoring Efficiently
Google Analytics is not always the best choice for your business; there are many other analytic tools that allow you to monitor your Web site traffic live. Live monitoring is a very important aspect of analytics. If you are able to see in real-time how your visitors find you in SERPs and what their response is after they see your landing page, I think there is no better way to find the keywords that really drive conversions.
Keyword rankings and keyword conversion depend on several other factors, ones I hope to cover in future articles. Kindly post your feedback and questions in comments below.