TIL my ferment needed less air to turn out right

I had this jar of pickles going for a week and they tasted kind of weird, not sour enough. I mean, I left the lid loose like I always do for other stuff. But then I read that some ferments do better with almost no air getting in. So I switched to a tight lid with just a tiny hole poked in it, and after a few days, the flavor changed completely. Idk, maybe it's just me, but I never thought air could mess it up that much. Now I keep it sealed tighter and check it every couple of days. My last try came out perfect, tangy and crisp. It's crazy how a small change fixed everything.