What gives weed it's potency?

Are the trichomes different from one that is high in THC than one that is lower in THC ? Or is the difference because one has more trichomes (of similar potency)?

It’s all about thc resin production some strains are just plain better/ faster at producing it( some even create streams of it of buds are dense enough) though the minor chemicals like thcv alter the feel of the high