The cards are just cards. Bits of cardboard in a box until you take them out and make a message with them. Like any tool, they do what you do with them. I think tarot works because it gives you symbols to work with when you’re trying to figure something out. The images and meanings help you see what you might already know but haven’t put into words yet. Anyone can read them, but whether or not they’re going to make sense really depends on how much effort they’ve put into studying the meanings and patterns.
The cards are never accurate or not. The reader is only as accurate as their ability.
When a reading feels spot on, it’s probably because something in those cards clicked with what was already in your head. The cards give you a way to organize your thoughts. As for mistakes in readings - that’s on us, not the deck. Sometimes we see what we want to see, or we’re just not ready to deal with certain things. I’ve had readings that made no sense at the time, but looking back, they were pretty clear.
The changes in your life happened because you were ready to hear what you needed to hear. The cards just helped you get there.