DefaultValue, as the name implies, means default value. However, this default value is not used for display. Its function is to display different values when the value set by the property (can’t be written in code or entered in the property window) is the same as the DefaultValue. For example, other values are bold and the DefaultValue is not bold.
DefaultValue can be roughly understood as a password or a secret code. Although it can’t be seen, it will give a prompt when the value is correct.