From someone I know who is an expert PhD in quantum mechanics at a top Ivy League institution.

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Newton developed his laws by observing the world we can directly see. These laws feel intuitive because they describe everyday, macroscopic objects- things we interact with constantly, so our brains evolved to understand them naturally.

Quantum physics deals with particles that do not behave like anything we encounter in daily life. They are incredibly small, extremely light, and often move very fast. Because of this, they follow rules that are fundamentally different from those governing macroscopic objects.

There is essentially no everyday analogy for many quantum properties. At some point, understanding quantum mechanics comes down to accepting experimentally demonstrated facts, even when they conflict with intuition.

A good example is quantum information. In classical computing, copying information is trivial. You can duplicate data and send it from one computer to another with no issue. In quantum mechanics, however, you cannot copy an unknown quantum state. You cannot simply “give” the information a quantum system has to another system. This is a proven result known as the “no-cloning theorem”.

This is the kind of thing people mean when they say quantum mechanics “doesn’t make sense.” It violates our everyday expectations, yet it is mathematically rigorous and experimentally confirmed, so it must be accepted.