Rule No. 265 from Guide to Composition (1919) by Royster and Thompson :
As a rule, do not employ euphemism -- the softening or veiling of an expression to avoid the use of words that seem objectionable or coarse.
Say went to bed, not retired; leg not limb; died not passed away. Facts that are really vulgar or coarse may well be veiled under a euphemism, or left unsaid.
The red ink above is the hand of Ferdinand Ruge on a 1972 essay, "How I Spent My Summer."
In note (1) at the top, Mr. Ruge points out that "non-motivation" is "A euphemism for damned laziness."