the.com/attrition

means A gradual wearing down or reduction in numbers through relentless, ongoing loss rather than a single decisive blow.

from From Latin 'attritio,' a rubbing against, built from 'ad-' (toward) plus 'terere' (to rub or wear down) — the same root that gives us 'detritus.' Medieval theologians used it for a lesser, scuffed-up form of sorrow for sin (as opposed to full-hearted 'contrition'), but by the 17th-18th centuries the word had drifted into military use for literally grinding an enemy down through sustained losses — and from there into offices and industries, where it now quietly describes staff who leave and are simply never replaced.