Is it difficult for some people to say "thank you"?

I don't know why it is not so hard for me to say thank you to people, especially if they deserved it. It is because I have learned to say thank you to people who has helped me or doing something good to me, my mother really implied in this attitude so much, because it is a way to show politeness towards people. But I don't make a thank you comment so much, because it is a little bit difficult to make a thank you message in this forum, because it is not allowed to make such thing here LOL

I always say thank you to every one that helps me. But try to understand that sometimes we forgot to say for some reason. It maybe, he was hurry and all he think is the business or any party his gonna mess. I myself done that and if your mind no longer busy thats the time you remember that you forgot to say thank you. And if it was happen to me I will try to say thank you by the next day cause I was hurry yesterday. Thats it, its simple...

hmmm...sometimes it happens. Just like a smile. it is so magical and simple yet it is often not returned. Lets be compassionate for those...they are not realizing the magic in saying "thank you" and smile.