Websites often serve multiple purposes such as lead generation, e-commerce, customer service or application delivery.
For example: a SaaS company may have a marketing site for showcasing its product and attracting new customers. This company also has a login to the application area, where existing customers login and use the product online.
However, to measure the site performance correctly, those 2 audiences must be separated, as not to inflate the marketing site with irrelevant usage data and vice versa.
To achieve this, we can use Google analytics’ custom variables. We can tag, for instance, registered users as a distinct group, and then discard them for analysis of the marketing site performance. This can be done, based on their cookies, even if they are not yet signed in! So now you’re tracking and analyzing your conversion rates for the right group of site visitors, and can actually see it’s real performance trend.
Beyond distinct audiences companies often have distinct web properties such as blog, forum, different product,…etc. Firstly, it make sense, tracking wise and architecture wise to place them in separate subdomains. Secondly, as far as Google analytics tracking, it make sense to use a unique code for each propety/subdomain individually. The benefits include: