Earlier we were used to track the entire journey of user visits i.e. If the users have visited multiple pages before the submission -> We used to capture these visit details against the lead after the conversion -> By default after the conversion every page will be tracked.
But recently there is a change in the before-conversion tracking mechanism[* Only in case of API's]
i.e. Before conversion, we'll track only the First time visit page details but not all the page visit details(* In case if the users are visited multiple pages before the submission) but however after the lead got converted we'll track all the page visits made by the users.
Note: Above explanation applies only the leads are getting created through API's.