By using a VISITOR scoped segment, you are pulling back all hits from Visitors who interacted with the campaign at any time during your reporting period.
Let's look at a simple example (I'm not sure what your expiry is on your campaigns, I'm going to assume this is tracking code and 7 day expiry):
Visit 1 (campaign X) - June 1
- Page 1 (campaign X is set)
- Page 2 (campaign X is maintained, but not set)
- Page 3 (campaign X is maintained, but not set)
Visit 2 (no campaign) - June 3
- Page 4 (campaign X is maintained from previous visit, since it's within 7 days)
- Page 5 (campaign X is maintained, but not set)
- Page 6 (campaign X is maintained, but not set)
Visit 3 (campaign Y) - June 5
- Page 7 (campaign Y is set, overriding the previous X, despite within 7 days)
- Page 8 (campaign Y is maintained, but not set)
- Page 9 (campaign Y is maintained, but not set)
Visit 4 (no campaign) - June 10
- Page 10 (campaign Y is maintained from previous visit, since it's within 7 days)
- Page 11 (campaign Y is maintained, but not set)
Visit 5 (no campaign) - June 24
- Page 12 (no campaign - nothing set and outside of 7 day expiry from when Y was set)
- Page 13 (no campaign)
Now, let's say you are pulling a report for all of June, if you are looking for "VISITOR with Campaign Y", you will get all the above pages (1-13), since your Visitor saw campaign Y on visits 3 (explicitly set) and 4 (maintained due to 7 day attribution). Don't forget, even the same visit could have multiple campaigns... I started from social media campaign, got an email while I was on the site and clicked through from that email.... 2 campaigns in 1 visit.
So what are you trying to find? Don't worry about the metric you want right now... the metric used with your segment is unrelated... Segment scope is about what hits you want to return in your data set.
Are you looking for:
- Visits that have Campaign Y attribution?
- Or Visits that explicitly came via Campaign Y
- Just the entry hit with Campaign Y?
Understanding your needs will help us to help you build the correct segment.