>>10222893> There's probably a bit more to it than "memorable, interesting characters", because I've seen FAR too many good series with this in mind that flopped (Operation Aliens, Mighty Max, Captain Simian, etc).It is mostly a combination of various factors.
Good characters, cool looking, good toys, competition, good value for the price, avaibility, good advertisments and willingly parents.
For example Star Wars, Spider-Man and Pokemon sells everything better. But often they just plan it to sell it for 2-3 years. Because that is the attentionspan their customers have. I mean that is when the next new thing replace the current stuff.