Why can't newscasters pronounce (and use) words properly?

I’m looking, as clearly stated, to ask why people think that newscasters who are only moderately skilled at pronouncing and using English are hired and renewed by the networks.

I specifically asked if we could discuss this outside of the discussion of what is and isn’t “proper” pronunciation and usage, as that is a whole separate and unpleasant conversation. If you can’t grant my premise that such a thing exists, you are hijacking this thread.