Circulating around the net:
Q. How many proofreaders does it take to change a lightbulb?
A. Proofreaders aren't allowed to change anything; they can only query.
Q. How many copyeditors does it take to change a lightbulb?
A. The last time you asked this question, it was about proofreaders. Fix?
Q. How many developmental editors does it take to change a light bulb?
A. Is the lightbulb intrinsic to the plot? If so, consider POV; dramatic tension might be improved by focusing less on the lightbulb replacement and more on the tragedy and pathos of the dead bulb. Finally, if electricity is part of your world-building, consider mentioning it earlier in the story. Lightbulb-changing out of nowhere could confuse your readers.