@birdsatemylunch
cards from me in Japan to USA might have been damaged more or less too but people from USA have not mentioned anything personally to me. Probably because they are used to it or something about the automatic sort machines there ?
i was once told personally about a damaged card officially. it was sent to Austria. the card was a bit thin and slighly big in size. it arrived there in a rough condition. here is the image :
So, I posted this thread nearly two years ago.
Since then, I nearly always post mails through the postal offices as I still am afraid the mails I post through postboxes from here could be damaged…
I still see people in Japan putting small packages and/or heavy mails into postboxes at once, and I go like, oh no… 
Are the cards you have been receiving from Japan in good condition or… ?
I’ve never received damaged mail from Japan. I have a few Japanese penpals who sometimes send a few items with their letters and they always arrive in good condition 
None of the cards I received from Japan have been damaged.
I just received a letter from my pen pal in Japan. Great condition, including the wax seal that was on it.
All my japanese cards arrived perfectly fine. I got an envelope from you the other day and it was also fine. 
All the cards I have received from Japan have arrived safely and in good condition 
Hi, thank you all, so far.
I am now a bit relieved. But if any of you keep receiving damaged mails from Japan, please do let me know.
Even after surface mail, i received my mail in perfect condition.
Same as @Anurag - even by seamail, all the cards have arrived in good condition. (Actually, the only piece of mail that was a bit damaged was a big parcel).
I cannot remember a single damaged postcard from Japan - everyone of them were in good condition 
Same here - never received a damaged card from Japan, neither official ones nor from swaps and forum activities.
My postcards from Japan arrive perfect! 