Now, there can be a number of reasons why visitor’s tracked are less than expected. Following is the list of such reasons:
1. In case you are measuring visitors in VWO in comparison to visitors in GA or other analytics software, you should be sure that you are measuring absolutely unique visitors in the analytics tool also. In VWO we only measure absolutely unique visitors and the default cookie life of VWO is 100 days, any visitor that comes back within this time period is not considered unique.
2. In case you are using async code of VWO, it might be caused by low timeout values. In the async code of VWO you will observe two parameter settings_tolerance and library_tolerance with values equal to 2000 and 2500 respectively. These are timeout values of VWO code and are in milliseconds. In case you feel that your visits are less than expected, you can increase the timeout values to include users with slow internet connections.”
In addition to these well defined reasons there can be some user specific reasons:
2. In case a user has cookies disabled on his browser, he won’t be included in the test.
3. The URL(s) on which you are measuring the traffic inside GA(or any other analytics tool) should be the same URL(s)(test page pattern) on which you are measuring the traffic inside VWO.
4. Always look for the absolute unique visitor count inside your analytics tool instead of simply visitor count. The definition of visitor count in many of the other analytics tools may be different from that in VWO.