This might be an extreme example of a maxim.
I was dimly aware of a novel written without the letter “E”. Recently saw a mention of it and looked it up.
"Gadsby" is a novel written by Ernest Vincent Wright in 1939.
More notable, for me, is an account of what the author did to make this happen — he tied down the letter “E” on his typewriter.
Think about that the next time you feel too constrained while creating something.