Impressions typically refer to the number of views or visits your profile or page received during a certain time period. For example, I received a few hundred impressions on my Clarity profile this past month, but as you may also see I don't get calls, that's because people email me or google me instead and reach out to me or my marketing agency www.unthink.me that way. If you are trying to grow calls, don't take that approach, instead consider SEO value, and see it as inbound generation. I get a lot of great results from Clarity, but I have been here since it launched. I have also been on Quora for a while now, just last month I received 4k+ views on my responses and profiles, but as far I know we haven't received leads from any of the answers I have published there, I know they are helping people because of the up likes and the follows and the number of views. Impressions are only basic data that make a larger picture - regardless of what you are expecting out your effort. :)