Why do the Mountains give us echo according to greek mythology?

http://www.loggia.com/myth/echo.html this website gives a detailed answer. The short answer is Echo is a nymph who made Zeus's wife Hera mad. Hera cursed the nymph so now she can have the last Word but only if someone else speaks first - Echo lived in the mountains and hills so you will only hear her speak to yo in the mountains and hills