Why do some ऐनीमे pick out English names for the characters instead of Japanese names?

It depends on which company owns it.They probably think that the little kids won't understand the names.

There are some ऐनीमे like Case Closed/Detective Conan where the American distributor changed the names to English names because they thought that made the दिखाना और acceptable to US audiences.

There are also ऐनीमे like Cowboy Bebop and Trigun where the characters have non-Japanese names from the start. I suppose that's because the characters aren't from Japan. Bebop takes place not in Japan, but in outer space, and Trigun on a Wild West type planet.
This is all my guessing--I'm not a professional "Answerman" (Or Answerwoman) like they have over at ऐनीमे News Network.