Another perspective; can you call yourself a true entrepreneur if you haven't had more than one entrepreneurial endevaour (I'm not talking that you need to have IPOd a tech company before but rather had a lemonade stand as a kid and vice versa)?
which suggests to me that debating over labels like "true entrepreneur" (or not) or "serial entrepreneur" (or not) is a waste of time.
The same discussion also smacks of a sort of elitism that I associate with the idiots to run around talking about what metal bands are or aren't "tr00 kvlt". None of this strikes me as very productive.