Because some people realise that in order to obtain something they have to do something for it themselves. Others believe everything will be spoon fed. They are usually disappointed, and full of accusations about the people who "did not give them the chance".

1) There are specialists in any trade. One possible trade is a language-specialist. Those people will know languages very well, for example many languages or specific ones in great detail. Having interest in leaning languages in general will help doing so :) Specialists of any trade will leave you shocked-and-awed in trades you're only "amateurish" in. 2) Otherwise, people might grow up in countries with 3+ native languages, or in multilingual families, and have to learn them at a very early age. Those people will have it much easier to learn "just" an additional language. Learning multiple languages at an early age will dramatically improve your capabilities to learn additional languages later. Has to got to do something with the brain-structure.

Cause there are two types of people: 1.those who want to learn more than two languages and learn it. 2.those who do not want to learn more than two languages and do not learn it! correct me:d