For You Blue is a song by the Beatles, written by George Harrison and released on their 1970 album Let It Be. Glyn Johns and Phil Spector were two of the producers who worked on the album, but they had different visions for the sound and style of the songs. Johns preferred a more raw and live approach, while Spector added orchestral overdubs and effects. Glyn Johns mixes were all rejected, and Spector's version was released as a single and on the album. 

But was the Glyn Johns production of For You Blue really worse than Spector's? 

To facilitate the comparison, we play the Glyn Johns version in the left channel, and Spector's mix in the right channel. It is evident that Johns liked Harrison's guitar, which is almost absent in Spector's mix. Much of the instrumental mixes are similar, but Spector includes a new version of the vocals. These were recorded after Johns left, so these new vocals were not available to him. 
But overall, were they right to reject Johns mix?