It looks like Analytics ID (v94) isn't available on all hits, therefore the Time Spent metric will be limited to only the hits with that dimension.
Thank you for answering my question.
I have another few queries that is why visits (metric) is showing same for all the dimensions.
Please refer the screenshot for visits.
I have used the different dimension but visits metrics is showing same date for all dimensions.
Because in order for any dimension to show against a visit, there must be a minimum of one hit in that visit.
Let's look at a few simple examples:
Scenario 1 (v94 is a "Visit Level" expiry)
The first page view was missing a value, but within the visit, eVar94 was set, therefore Visit is counted
Scenario 2 (v94 is a "Hit Level" expiry)
The first page view and the Action 4 are both missing a value, but within the visit, eVar94 was set, therefore Visit is counted
The only way that you could have an overall visit (your first image) have more visits then when looking at eVar94 against visits, would be if every hit in the visit was missing a value.
Do you have "unspecified" or "Low Traffic" filtered out? Might be that is what is making the delta. Low Traffic will often happen for ID based dimensions if you go over the 500K monthly limit.
Another thing to look out for is your dat range selection vs your dimensional month items in your table. See the attached image: