Resting before tired feels like giving up

so i know the rule. proactive rest, avoid the window, stop before you hit the cliff. i spent years telling patients exactly this. but there’s something i didn’t fully get until now. when i’m still feeling mostly ok at hour 2.5, and the pacing log says “stop here,” something in me says why. i feel fine. imo shouldn’t i feel tired first? shouldn’t i rest after i’ve done something? like stopping early is wasting time. or maybe it’s just… wrong. the PT part of my brain keeps asking: isn’t this deconditioning? am i wrapping myself in cotton? but then tuesday i ignored the log and stayed at 3.5 hours. felt ok. crashed wednesday. my question: does that gap b/w “feeling fine” and “actually hitting your limit” ever close? or is it always this weird leap of faith - stopping when everything says go?