Newbie question about deleting apps and internal storage...

[sushifor5]

Why when I delete an app does my internal storage indicator (I'm reading it from Quick Settings) not reflect the amount of space the app was taking?

I just deleted an app that said it was 2.5 mg and my internal storage only increased by 1 mg.

Do apps leave traces behind when we delete them? How do I get rid of an app completely and regain my storage capacity?

Thanks!