One problem is that so many cars have now been asked that only the really obscure ones are left.. Perhaps it is now time to allow re-posts of cars but not of the same picture. The original poster and solver are probably Pros or Experts by now and most of us will have forgotten the answer by now and have to go searching anyway.
Another problem is that most puzzle posters have learned so much on here that the puzzles they post are simply too hard for the rookies and they get put off.
As a typical example of what I mean, one of the current set of Rookie puzzles asks for:
For one point, please tell me the make of car, the names of the two men on the right of the photo, and the date and place. That's all!
Fair enough at Expert or Pro level, but at Rookie level the question could be simply "Name the car?" and "Name the two men" and "Time and place" either for bonus points or added at the Expert or Pro stages.
And avoid the horribly patronising "The base car is easy" or "The base car is obvious" which will put immediately put off anyone who doesn't know it. It's better to say something like "No points for the base car but for the point give ~ "
