This quote by Cyril Connolly suggests that although vulgarity may not be pleasant, it is a vital part of life. Simply as garlic is an important active ingredient in a salad, indecency is an important part of life. It is a reminder that life is not constantly best which there are some undesirable aspects to it. Indecency can be seen as a reminder that life is not always simple and that there are some hard and unpleasant minutes. It can also be seen as a tip that life is unforeseeable and that we need to not take anything for given. In this method, vulgarity can be seen as a pointer to appreciate the excellent minutes in life and to be gotten ready for the bad.
"Tomorrow is the most important thing in life. Comes into us at midnight very clean. It's perfect when it arrives and it puts itself in our hands. It hopes we've learned something from yesterday"