How could/would all these coins work together?

[WilliamTryingTo]

I'm just wondering, with all these coins out there and people just buying in thinking they will all go up in value.. But how would it all work together? How can there be more than one coin that's truly successful for a long time?

Are "normal" people really interested in having ten different coins, each with their own purpose?

Another thing I don't understand is the constant price changes, how will it be kept stable enough for people to stay interested in a certain coin?