Slow learners or poor teachers?

A quick look at a random sampling of ratings shows some interesting stuff. Of the 92 club members with last names beginning with K - M, their ratings break down as follows:

7 have ratings on at least three different types of craft
15 have a Tech rating plus one other rating (mostly sailboard)
32 have a Tech light rating only
38 have no ratings at all

Thus, three-fourths of all club members never advance any further than a Tech light rating! Importantly, these ratings statistics are a snapshot of club makeup that will not change appreciably from one year to the next. Annual memberships can be bought at any time, expiring exactly one year later. Thus, although some of the people who joined early this year will have more rating(s) by September or by 2009 (if they re-join the club), the memberships of other people who have ratings will have expired in the meantime.