Why are there so many dialects?
to many dialects
4 Answers
I also think that since language is dynamic, it is continuously influenced by the culture and every-day life of people in each region. Many expressions, idioms and words well reflect the conditions of life during the period of their "birth" and underline, as well, differences which arise due to geographical reasons. It is not random, for example, that in Mexico you can find expressions where words related to cactus, beans, corn etc are used -these were and still are parts of their culture and every-day life. It is also not random that different dialects exist not only in different countries but even in different areas of the same country.
Primarily, dialects result from geographic isolation. The isolation needn't be absolute (such as an island's boundaries), it's enough that it make travel difficult (obviously, before modern transportation, a river or a couple of mountains was enough).
because of the beautiful diversity of the world and language.... 
It's for the beauty of diversity!!! In Japan, each prefecture has it's own way to say certain things (although everyone still uses standard Japanese). For example, Osaka is famous for it's dialect. Instead of saying "nande desuka?" for "why is that?" they might say something like "nandeyanen?" Dialects and other language differences can give each place something to be proud of.
