Ionic cache doesnt work

i need cached views but ionic doesnt really work on caching stuff at all.
i grabbed blank app from get start and manipulated a bit. see my code
i put two console.log in order to see whether ionic launch them every time that i hit their route or not.
here is the thing $urlRouterProvider.otherwise(’/index’); controller that was binded to this route has caching ability but single controller dose not have. whyyyyyy is that . it drives me crazy