I like to explore Postcrossing as a system (mass phenomenon), find correlations of its factors, identify triggers of influence in it and give feedback on this in the form of an explanation of the reasons and recommendations for improvement.
I have a lot of experience in optimizing the work of similar systems.
In my profile, I quite openly wrote this:
“What I love most about Postcrossing is the next million countdowns where we have to guess when the registered postcards number will reach the next millionth level. Join us!”
I think it’s great that postcrossing provides so many other interesting reasons to participate besides sending and receiving postcards