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I was reading this, where it is mentioned that some quantum theories can have no classical limit or even more than one classical limit.

A possible example might be quantum spin, which doesn't have a classical analog. What is the precise condition (does it arise solely on imposing $\hbar \to 0$, which I am not able to see for quantum spin) that determines the number of classical limits of a quantum system?

What are some other examples of this, especially of systems having more than one classical limit.

I was reading this, where it is mentioned that some quantum theories can have no classical limit or even more than one classical limit.

A possible example might be quantum spin, which doesn't have a classical analog. What is the precise condition (does it arise solely on imposing $\hbar \to 0$, which I am not able to see for quantum spin) that determines the number of classical limits of a quantum system?

What are some other examples of this, especially of systems having more than one classical limit.

I was reading this, where it is mentioned that some quantum theories can have no classical limit or even more than one classical limit.

One possible example might be quantum spin, which doesn't have a classical analog. What is the precise condition (does it arise solely on imposing $\hbar \to 0$, which I am not able to see for quantum spin) that determines the number of classical limits of a quantum system?

What are some other examples of this, especially of systems having more than one classical limit.

I was reading this, where it is mentioned that some quantum theories can have no classical limit or even more than one classical limit.

A possible example might be quantum spin, which doesn't have a classical analog. What is the precise condition (does it arise solely on imposing $\hbar \to 0$, which I am not able to see for quantum spin) that determines the number of classical limits of a quantum system?

What are some other examples of this, especially of systems having more than one classical limit.