the.com/false summit

means A point on a climb that looks like the top but, once reached, reveals more mountain still waiting above.

from Not an old word at all — it's mountaineering jargon, first showing up in climbing accounts in the 1800s as people wrote about the demoralizing trudge up ridges that kept pretending to be the summit. No myth here, just the literal compound 'false' plus 'summit,' coined by climbers who'd been burned by exactly this trick, and later borrowed by everyone who's ever hiked, dieted, or run a long race and thought they were almost done.