Indonesians don't like conflict. Friendly, outgoing and peaceful are the norms for interaction. For this reason, saving face and not being caustic are very important for travelers to remember.
People in Indonesia embarrass easily; so it is considered very rude to do things that would embarrass anybody. These include raising your voice or making accusations. Problems are publicly treated as issues to be solved in concert with others, and ego-based or emotional outbursts are inappropriate.
This cultural principle, known as equanimity, has roots in Eastern religious practices like Confucianism and Buddhism.