In reply to lithos:
I too have only completed one, and it's the massively unimpressive Top 23 UKC Climbed Climbs. But still, only 23 other people are shown as having done it.
I've only done 60% of my own Rog Wilko's Neglected Gems in The Lakes, but since only 13 have subscribed to it and it includes a lot of esoterica it's no wonder no-one has completed it.
Otherwise I've only ticked 75%+ of 3 lists.