I would like to introduce an phrase.
That's "Osewa ni natteorimasu""Osewa ni narimashita.""Osewa sama desu".
We often use these expression on business.
Whenever I get a phone at office, I would say this phrase.
Osewa means "take care of".(Probably)
The phrases above means like "Thank you for taking care of me (us) everyday.".
We say these phrase even we do not know the customer or the client well.
We also say these phrases not only when we speak on the phone
but when we face people.
I think this custom tells Japanese people's way of thinking.
We are taught in the society that we can not live without other people's help.
When I use these phrases in our daily life, I do not think of the meaning deeply.
However, these phrases may have deep meanings in a background.
Thanks for reading!!