I disagree with the opinion that Miles was trying to "cash in" on the trend to go electric; or, that he was envious of their success of artists such as Sly or Hendrix. First of all, by the time that he released "Bitches Brew" he was a wealthy man and he also knew that his place in music history was well established. He admired and respected Sly and Hendrix and saw "going electric" as a new and different outlet for his creativity and not simply a commercial opportunity. I think that, in spite of his star status, the depth of Miles's genius is still underestimated. IMO, as music lovers, we would do well to always give an artist of the stature of Miles (there aren't that many) the benefit of the doubt; it can only serve to help us grow as music lovers and we should judge with a sense of humility. IOW, when the artist moves in a direction that may not be to our liking, we should ask ourselves "what am I not hearing?", instead of being quick to dismiss it as a move in the interest of financial success without real artistic merit.
http://m.youtube.com/watch?v=dc7qiosq4m4
http://m.youtube.com/watch?v=dc7qiosq4m4