OK, so this is sort of a pet peeve of mine: Japan is a polite country. It isn't a uniquely polite country. My post is a bog-standard American businessman pleasant refusal for a request without saying "Your business is unprofitable so #"$& off and die."
Relatedly: Americans have been known to say one thing but believe another. Gasp! I actually had a Japanese coworker who was flummoxed when that happened to him -- he said, in as many words, "What is the world coming to?! We invented [the Japanese word for the distinction between what one says and what one actually believes] and now even the Yankees are doing it?!"
A management course I recently took referred to this as the "integrity snowman." Think of three big snow balls labelled "what I think," "what I do," and "what I say" stacked on each other :-)
The challenge is to keep them balanced in a straight line.
Relatedly: Americans have been known to say one thing but believe another. Gasp! I actually had a Japanese coworker who was flummoxed when that happened to him -- he said, in as many words, "What is the world coming to?! We invented [the Japanese word for the distinction between what one says and what one actually believes] and now even the Yankees are doing it?!"