when does autopark not activate?
Pretty much all the time. Auto park is kinda iffy as to when it sees a spot and offers to park. Sometimes it's inappropriate, like when you're at a light and it sees a gap in between the cars to your right that are waiting to make a right turn.
I've found it useful in both parallel and perpendicular parking situations. It requires a space between two cars to operate. If there is an open space, say between painted lines, it does not recognize it.
@ jefferymjackson1, did you mean to ask WHY instead of when?