Speaking well speaks to who you are. I remember in grade school, some children would teach classmates who used standard English, mocking that they sounded “proper.” The quip was actually used as an insult. I was more often than not at the end of at the “proper” jokes. Oddly enough, this really didn’t bother me.
My mother always reinforced using correct English and even reprimanded my brothers and me when we didn’t. Despite popular music and television, using proper grammar was always okay in our world. You can express yourself and everything about you while speaking well. This is not to say that you will never misspeak or dialect won’t take over--being from Louisiana, I know all too well about that.
You want well for everything in your life—eat well, sleep well, and speak well; it makes a difference.