how did you decide what to collect?

how did you decide what to collect? hmm iv collected alot of things i have normale collections like rocks and seashells and when i was little i collected over 150 raggedy ann dolls ( that are now in my attic collecting dust )  when i got into middle school i was trying to think of something diffrent that not many people would think about collecting, along with something i could relate to. so i decided on dragons since i ( at the time ) didnt think many people collected these wonderful gothic reptiles.