Why are phone calls recorded with such bad quality?

We have digital TV and GPS systems and text messages that sent in a matter of seconds and can send emails all across the world in amazing quality. Yet whenever they play, for example, a Police recording, on TV, the quality is so ridiculously horrible that they need subtitles to make sense of the grumble. Speaker phones on cell phones always produce a weird sound and distort audio. Why is it that phone's use such bad quality. I understand the speaker phone to some extent, but why can't police use better quality phone calls? It just doesn't make sense to me how our audio connections are so bad.