Barn find?

The term barn find seems to be in fashion again at the moment.
What does it mean? What determines a barn find?
A car that was parked in the barn during it's active life time and then forgotten about or a car that has been stored in a barn later in life an then neglected or maybe a car that has been filed in the barn waiting for it to gain in value.
I mean you can't find a car if someone knows it's there, can you?
I believe this Jaguar has been left here in more recent times moved here in this state and kept here for cheap storage waiting for the right time to turn a usable profit.
It was parked next to a Maserati.