The scarcity of Myscene Dolls

I was just curious if anyone can explain why MyScene Dolls are so scarce and hard to find even on resale sites like eBay is it because they were really that less popular then Bratz and Barbie or because less were produced world wide? I know it feels like these days Bratz is a slow burn and I’m also wondering if that’s how it was when My Scene was popular (2003-2006) did these ever sell out fast or have similar issues to current Bratz releases? Can’t wait to hear what you think! :)