This number tells you how many times your content has been seen by
other people, including your Photos, Posts, and the page itself.
As stated on this article here
Posts are counted for any view of them in any Google+ stream. A viewer does not have to click on or otherwise engage with a post for it to count as a view. So even if the viewer scrolls by the post in her stream, a view is counted. Basically, the post just has to have been seen on someone’s screen.
All shares of a post that are seen by others count as views, both for the sharer and for the original poster.
Posts that become recommended content in others’ streams because someone +1’ed them can count as views for the original poster.
Embedded Google + posts also can increment this view count. That’s because a post embedded in a site page using the post’s embed code displays in an iframe, which means it is actually being viewed on the plus.google.com server.
Photos/images must be “opened” only need to go by in someone’s stream (or be seen on Blogger, Picasa, or Chromecast) to count for a view.
Profiles & Pages only count as a view when someone opens them in their own tab or window.
View counts may not be exact.
View counts are not updated in real time.
Views are counted when posts are viewed in communities.
Views are counted whether or not the post was shared publicly or
privately.
Views of a Youtube comment integrated with your Google+ count may
count too.
Images on Blogger blogs are hosted on Google+, and thus views there
count as views for the associated Google+ profile.
Views of images on a user’s Picasa account count as views for their
Google+ account.
Google+ images shown as Chromecast screensavers may count as views
for the profile that posted the photo.
View counts for pages have replaced the +1 button and associated
count on the page. But the page’s total +1 count is still in the
Google+ API, and still appears on on-site buttons or badges that
display it (at least for now).
Google maintains an interesting symbiotic relationship with its users, especially users who generate content (UGC) that Google makes use of. Some of that content is just indexed by Google (Search, Maps). Some is hosted on Google properties (Google+, YouTube).