Hi
Following could be the possible reasons:
1. I hope link doesn't open a js overlay which might result into higher clicks than pageviews.
2. If its redirecting to other page , check in debugger if request is not getting break (minimum 500 ms required to complete the request).
3. No java script error on the page.
4. if request is sending by ajax please check in the debugger that sitecatalyst request is been captured properly.
Regards
Devinder