My CCLeaner (multiple versions) often claims to remove more trackers than it discovers but every once in a while (I haven't found a pattern yet) it will find a lot of trackers but only remove a small number of them and on a rescan it will not find the other trackers that it did not remove.
don'tFor example, it may find 1100 trackers but only remove 5 and subsequent rescans doesn't locate any of the other trackers.