So now I wonder, why did the medevial era (at least knights) seemed to favor metal armors? I doubt it was less labour intensive, metal was harder to get for sur

So now I wonder, why did the medevial era (at least knights) seemed to favor metal armors? I doubt it was less labour intensive, metal was harder to get for sure and it was probably way heavier. Was the knowledge forgotten? It seems unlikely but it might be so. Was the psychological effect of metal armor better wether at creating fear in the enemy or at creating a feeling of being safe? Would love to know more about this.