Your site's metrics can tell you what is working and isn't working in your marketing efforts: If you run a business website, it is essential you monitor your site's metrics.
Referrals
One of the most important metrics to monitor is your referrals. Referrals tell you where visitors are coming from, including what links they followed to arrive at your site.
This can be a big help in knowing where your marketing efforts are succeeding and failing.
The information will allow you to spend more time developing a marketing strategy that works. All too often, web marketing professionals simply throw everything at the wall to see what sticks. Online marketing needs to be a targeted science and not simply a shot in the dark.
Bounce Rate
Bounce rate is the rate at which visitors came to your site, looked at one page, and left.
It can be an indication that you are not attracting their attention while they are on the site, meaning you should think about tweaking some things. But it may also be that your landing page is too cluttered, or that your keywords are bringing in visitors for the wrong reasons. For instance, if you sell kitchen utensils, yet you have "food" as a keyword, visitors that come to your site through the keyword "food" will not find what they are looking for, and they will leave.
Understanding why visitors leave is as essential as understanding why they arrived.
Conversion Rate
You started your business to make money, and to make money you need customers. So, converting visitors to customers is your number one goal.
When you have many people visiting your site, but few are purchasing products, you know there is a problem somewhere.
Potential problems could lie in your site's layout and design, your checkout cart system, or a number of other places.
Pinpointing why visitors are not becoming customers is crucial in building your site's success.
Unique Visitors
The number of unique visits is a measure of success when combined with referral information.
The number of unique visits, as well as the number of return visits, tells whether or not your site is being noticed at all.
When you combine this statistic with referral links, you can see if people are visiting your site through links you have placed online, or whether they are coming straight to your site by typing the address directly into the address bar. This can be an indication of where your marketing efforts are paying off.
I believe the most important one from the list is Conversion Rate. As if you can work on getting your conversion rate to where it should be, Automatically your bounce rate would go down.