When I mentioned to some friends that we all have accents, most of them proudly replied, "Well, I speak perfect English/Chinese/etc." But this kind of response misses the point.
More often than not, what we mean when we say someone "has an accent" is that their accent is different from the local one, or that pronunciations are different from our own. But this definition of accents is limiting and could give rise to prejudice. Funnily enough, in terms of the language study, every person speaks with an accent. It is the regular differences in how we produce sounds that define our accents. Even if you don't hear it yourself, you speak with some sort of accent. In this sense, it's pointless to point out that someone "has an accent", We all do!
Every person speaks a dialect (方言) , too. In the field of the language study, a dialect is a version of a language that is characterized by its variations of structure, phrases and words. For instance, "You got eat or not? " (meaning "Have you eaten? ") is an acceptable and understood question in Singapore Oral English. The fact that this expression would cause a standard American English speaker to take pause doesn't mean that Singapore Oral English is "wrong" or "ungrammatical". The sentence is well-formed and clearly communicative, according to native Singapore English speakers' solid system of grammar. Why should it be wrong just because it's different?
We need to move beyond a narrow conception of accents and dialects—for the benefit of everyone. Language differences like these provide insights into people's cultural experiences and backgrounds. In a global age, the way one speaks is a distinct part of one's identity. Most people would be happy to talk about the cultures behind their speech. We'd learn more about the world we live in and make friends along the way.