In Workspace I'm seeing a large amount of Unspecified as Page (dimension) specifically under these conditions-
I created a freeform table with Page as the dimension and Page View and Visits as metrics. Results: Unspecified doesn't appear in the list of pages. This is the OOTB Page dimension, not a custom evar or prop.
I duplicated the above table and removed Page View from metrics so now it's just Page and Visits. Results: Unspecified page has 39.6% of Visits; Unspecified is the top (has the most visits) in the chart.
I created another freeform table this time with eVar1 which is page name; this is set up in Launch using a data layer and collected pretty much on every rule but in short it is the same as Page. When using eVar1 Page Name as dimension with Visits as metric, there is no Unspecified.
Why is it when I use Page dimension with Visits metric results in 40% Unspecified visits?
I tested our implementation via Chrome Console>Network and can see pageName having a value on every hit. I clicked around for a while but every hit has a pageName value. How is it possible that there are 40% of Visits with Unspecified as Page? Am I interpreting this incorrectly?
Based on my understanding, you are seeing 'Unspecified' line items when using Page dimension along with the Visits metrics because there will be some Visits where the visitors are landing to your web site via the custom link calls i.e. s.tl(). In the Analytics report, we don't show the Page Name or Page URL for the custom link calls. This is working as per the current design of Analytics.
Also, you don't see any 'Unspecified' in case of eVar report because you might be capturing the Page Name in case of custom link calls as well.