What is the importance of Annotations in Google Analytics?

One of the most important things to remember in the field of Internet is that, every website/blog is unique. Because there are so many factors playing in. Each website has its own unique content, diverse businesses, visitors etc. The point is what works perfectly for one website may not work at all for the other. A particular  marketing strategy might be suitable for one website,but not for the other.  Though definitely there are some basic funda for websites but there are no universal rules. So, what do you do?

The answer is Test,test & test. Only testing and experimentation will show what is right for your website. Then the role of annotations comes in. Whenever you implement any new marketing strategy, you mark an annotation as shown in the figure below. And you can keep track of the changes before and after the annotation. This will help you to find out which strategy helps you increase your visitors and which decreases.