As the title said. All these times I think that every countries have their rights to refuse any visitors and do not have to tell the reason. Reading the posts on another thread it looks like that my thinking is not a correct one.
So, lets assume that it is incorrect. Could anyone give examples of occasion some country reject visitor and the reason for it. May be start with your home country which should be the easiest.
Please note the plurals to indicate that giving reasons is the norm not the exception.