1. When an existing lead sees an ad & signs up again. Then it is difficult to list out with Lead source.
  2. When running remarketing ads, visitors from other sources like direct traffic, organic search etc, would have visited the website and bounced off without taking any action. When they see an ad again, fill it. It is difficult to identify the lead source. Because, LeadSquared captures the first activity source.
  3. Cross campaigns --> as in the lead first visited search campaigns, & then filled the display ad form. Conversions gets attributed to display ad in Adwords but in LSQ lead source will be marked as search ads.
  4. The conversion window you have chosen has an impact. Let’s say 30 days is your conversion window. I visited the site on day 1 , and didn't do anything. On 29th day, I visited the site again through some other ad & filled the form. Then the “created on” date in LSQ will be the 1st day. In Adwords it will be the 29th day, and you’ll see discrepancy.
  5. Now the conversion column includes cross device conversions as well. So, let’s suppose you are running ads on mobile, and someone clicked that ad, and visited the page, but didn’t fill the form. Next day, they see some other ads on desktop & fill the form this time. In such cases as well, you will see the discrepancy.  
  6. Let’s say someone clicks on an AdWord ad, and then 10 days later purchases from you.  Two days later you email them a killer offer and they click and buy on that one.  Then five days later that person goes to your site and makes a third purchase.  The AdWord ad gets three conversions.

I do understand and agree that many times a person needs a lot of exposure to a brand to make a purchase.  But to extrapolate that idea into the concept that every ad the person has seen within 30 days gets a credited conversion.The over-counting of conversions could be preserved if you take the time to have distinct thank you pages for all your different funnels.