I know why!

It just occurred to me why Singaporeans do not have a common identity or culture. Singapore has constantly been changing with the times to survive since independence and there was no prolonged period where there was no change. That and the fact that we have only been a republic for 40 years.
However having said that, who said Singaporeans do not have a common identity? When I was in HK, people could tell that I was Singaporean when I went shopping. There obviously must be some identifiable trait that we all share.