Assalamualaikum wbt and good day to all.
It is occurred to me, being courteous is a skill that required for my recent occupation.
Yes, nobody will know you, who you are, your appearance when you talked over the phone.
BUT, it still reflects you.
I did encounter some of this situation. Alhamdulillah, not from my side. :-)
Usually from the other side.
I did felt offended but suddenly I smile.
Well, maybe some of them having a bad day. Busy. Very busy. :-)
I'm not blaming them.
On the other hand, some young generations especially fresh graduates, (I was among of them),
lack of courteous, especially when dealing with people.
You guys shouldn't do it.
Just remember, when we talked over the phone, put ourselves in their shoes.
Maybe during our call, they have too many business to settle.
1- Introduce yourself.
2- Talk properly.
3- Respect the other side.
This is what I have learnt.
Suffixes thought: It is no that hard to be courteous.