Okay, since this has been officially declared #coloristappreciationday, here’s my two cents on why colors are so important. 
I don’t want to toot my own horn, since I’m usually my own colorist, but I don’t have much examples of other people’s colors on my drawings, so here it is.

In my process, pencilling brings only about a third of the overall mood and detail to the images I want to put on paper, and mainly due to the fact that I’m involved in all the stages, so I tend to skip certain steps on pencils and leave them to the coloring and shadowing treatment. So, while pencils set up the action and the main blocks of what’s happening, color is fundamental to give the image depth, mood and detail. Also, it´s great to accent stuff you forgot to pop and hide stuff you screwed up on the drawing stage. And that’s neat.

Case in point, this panel form “Cursed” my Hanuram short story for the upcoming kaBOOMbox anthology from Brand New Nostalgia.
There’s all sorts of examples of the importance of colors popping up today from real professional colorists, so go find them now, and if possible, hug a colorist today.