Personally, I write my review the day of check out. I like the map feature where I can track my travels (when it is working... which it isn't at least for me now but I find it a nice add on). I do it for every resort I stay at if for no other reason that to have a vacation history log with dates etc . It is something to look back on fondly. I also feel that it is the most important benefit of TUG. The downside is that your competition is free and has outpaced you and outspent you from a platform and usability perspective
. When TUG started there was no YELP, TripAdvisor, google reviews etc.
In my experience, the 20/80 rule usually applies to services like this where 80 percent of reviews are written by 20 percent of users.
That being said, one of the first questions I have on your 50% no review statistic, is how many TUG members who have no reviews have active listings on the marketplace?
e.g. could it be that a large chunk of your membership are people who are paying just to be able to advertise their listings on the site?
If you take all your paying members and divide them into few buckets:
1. Those who have no listings or reviews - (people who paid but are "inactive")
2. Those who have no listings but make reviews - Active members
3. Those who have or have had less than 2 listings in a year and have a review - Active member (I chose 2 or less to try to identify non-commercial you may have a better stat)
4. Those who have less than 2 listings a year and no review - Active member, non commercial
5. Those who have more than 2 listings a year and reviews
6 those who have more than 2 listings and no reviews
Maybe you will get a better perspective on the population because Those in bucket 1 are not using the service for anything other than the forum (if that) and somehow need to be engaged to go to the main website (maybe check their traffic patterns). I would guess that they will be very difficult to get to, especially if like me they generally use their cell phone (and as of now there is no TUG App for the main site that I am aware of).
Bucket 4 is probably the only audience you can actively target with benefit.
Bucket 6 will never be got as they are only using your service to gain access to potential buyers.