I was having trouble applying a colorscheme in vim. I copied over my vimrc and .vim directory from another computer, but the colorscheme was not applying. All other settings from my vimrc were loading, but not the colors. If I set the colorscheme manually or re-sourced $MYVIMRC, then the colorscheme applied, so it was very strange. echoing g:color_scheme threw an error.
There was a color scheme file saved in ~/.vim/plugins instead of ~/.vim/colors from a long time ago. It had never loaded, so I forgot about it. vim must load plugins after running the vimrc file, overwriting my set colorscheme.