As a suffix, "less" negates the meaning of the word to which it is appended. The effect may be pejorative, as in "heartless," "brainless," "senseless." It may be laudatory, as in "fearless," "selfless," and "dauntless." Or, as in "effortless," "listless," and "boundless," it may be nonjudgmental.
A uniquely laudatory change of meaning occurs when "less" is affixed to "time." The latter is not reduced or abolished; it is transcended. A timeless artistic masterpiece or scientific discovery is invulnerable to erosion by time. It endures. Its creators, the immortal geniuses, remain a source of wonder, and their creativity provokes much speculation and study.
One such study by Stephen Jay Gould1 attempts to trace the paths to great scientific discoveries, as exemplified by Darwin's theory of natural selection. In a penetrating analysis of Darwin's writings, Gould argues persuasively that neither inductive reasoning based on observed facts and performed experiments nor flashes
Vaisrub S. The Timely and the Timeless. JAMA. 1980;244(14):1610-1611. doi:10.1001/jama.1980.03310140068038