Why we all need to edit

I suppose dear reader, you could take this in more than one way.

For example, since I make images almost every day, editing is paramount to strengthening my portfolio.  When I pull images out of the line up, I do it because they don't blend with the overall aesthetic of what I'm presenting to the world, even though at the time I made them they may have.
I pull certain images in order to strengthen instead of dilute my message. Every now and then, I look through my website from the point of view of a newcomer and ask myself, "does my portfolio make sense?". "Is what I'm seeing a coherent message or is the message a jumble of disassociated individual images".  A jumble of images makes for a weak and unmemorable experience for the viewer. This is where editing and culling poor images becomes important.

If you are talking metaphorically, one could edit their circle of influence, their relationships with people they commonly associate with.  As the saying goes, you are the average of the 5 people you spend the most time with. I may have the number skewed a tad, but you get my point. If those 5 people are low energy, lethargic and always bring you down, you would do better to edit your crowd in order to improve your chances of happiness and prosperity. Editing is a good thing and should be taken on without hesitation.

Thinking of reducing your crowd of influence should never be thought of as a negative action. On the contrary, doing an inventory and analysis of what improves and what degrades your life is an essential skill. You may even go as far as to conduct an 80/20 analysis to home in on what exactly is making your life better, and what is simply draining your resources. 

As a photographer, I take editing quite seriously. One substandard image may be the only thing a portfolio is remembered for in a sea of gems. It only takes one sour candy to ruin a delicious cheesecake.
Never be afraid to edit. You'll be stronger for it in the long run.