My situation is unique so it would be difficult to put an exact time on when the hoarding / collecting really started. As most of you know, my father was importing pinballs in the early 50's, so I've been around them all my life. When I was in primary school, I used to come home and find NIB Bally games being stripped and contact being installed. There were two games that I wanted to "keep" for myself. KISS and Paragon. Both are in my collection. But it was not a "collection" until I had my own home. But the Business stopped in 1994, and all the games were collected from sites and placed in storage with the others.
The plan was to own as many games as I can - an addiction rather than a collection.