Further to having Google Analytics installed and setup to it's fullest potential, there are more customized Key Performance Indicators (KPIs) that you need to monitor.
Starting with the most basic numbers - is the total top line traffic coming to your website. Know the difference between a "User" and a "Session". A user is an individual who may have several sessions on your site in a given time period.
Another basic but integral understanding is the type of traffic coming to your site. There are only a handful: Direct, Search (Organic vs Paid), Referral. Direct is whereby a user literally types in your website address into their web browser. Search is coming from the search engines like Google. The first few results on Google that show "Ad" are Paid, whereas the following 10 results are Organic. Finally, referral traffic is when someone clicks on a link and is brought to your page. Social media is all referral traffic and even if you do an E-mail blast, much of this traffic is tagged as referral (unless you've enhanced your Google Analytics setup to track separately as E-mail traffic in it's own category).
Retention rate, the inverse of bounce rate, is the percentage of users who engage and stay on your site. The default parameters are that they clicked at least once, however this can be further customized to meet your needs such as only counting those who stayed on your site for a minimum duration and/or performed one or more actions. Benchmark is to aim for a 50% retention rate.
Conversion rate is ultimately one of the most important KPIs and you should know this number at all times. It is the percentage of total sessions that converted. Typically on an eCommerce site, a conversion is deemed made a purchase. However, setting up multiple conversions is highly advisable. Joining a mailing list and acquiring an e-mail address is a common conversion, as is downloading a white-paper. Overall for eCommerce, a 1.00% conversion rate is an initial benchmark to target. This varies among industries and even type of traffic.
Next, you must choose your attribution model. For example, let's say that a user first visits your site from Paid Search. He then returns 3 more times by Directly typing in your website. Finally, on his 5th visit he came from one of your E-mail campaigns and executes a purchase. Which traffic channel deserves credit for this conversion? Google has several different ways to track this. Pick ONE that is best for your business, and stick with it. See: https://support.google.com/analytics/answer/1662518?hl=en
For those doing Google Pay-Per-Click (PPC) online advertising, also known as Google AdWords, the most important KPI to watch is Return on Ad Spend (ROAS). Don't be fooled into thinking that Cost-Per-Click (CPC) is the only metric to know, as a keyword costing 5x as much but converting at 10x the rate delivers a higher return.
Since we mention CPC, this is the amount you pay to Google for each time a user clicks on your ad and comes to your website. They start at $0.10 and can go beyond $30.00, and sold via auction format. These prices can change dramatically over time, and are dependent on several factors: your competitors bidding on those keywords, the industry, search volume, the value of the associated product and placement of ad (e.g. guaranteed 1st spot vs 3rd or even 1st on 2nd page).
Average Order Value (AOV) is just as it sounds. This can certainly make a difference to your revenue and bottom line, even with the same volume of orders being processed. We've seen promotions such as "free shipping for orders over $xx" and intuitive cross-selling make a difference here.
Cost Per Acquisition (CPA) is your ultimate KPI that should be your guiding light on how much and where to invest your marketing dollars. This can varry greatly across various types of traffic. The ideal scenario is that your CPA is profitable from the very first purchase. That is, if it costs you $50 to convert one sale, and that AOV is $400 with 50% margin - boom! Since this is not always the case, there is one final KPI that must be considered. It is especially relevant to consumable products and wholesale businesses.
Lifetime Value of a Customer (LVC). Many customers come back and purchase several times in a year. Some products are subscription based. Determining the actual value of a customer should be strongly considered, especially when investing marketing dollars to scale and acquire new customers. It is important to note that often times a new customer may discover your website and purchase your products via Paid Search or some other Paid traffic channel, but as they become familiar with your organization, subsequent visits come in by Direct, Organic or E-mail.
Moral of the story - Know Your Numbers and be in the driver's seat of your eCommerce. Review detailed reports and run your business from anywhere. See below for a snapshot of Mynt's standard Reporting & Analytics. These and hundreds of other KPIs are what you need to know.