Why x:=CAS("x") = 0 ?

[Carlos295pz]

I know that doing this may not make much sense, since the use of CAS variables does not require the creation of an HP PPL variable with the same name, or even that they are created. But recently I could see how some people use it and I have doubts.

LOCAL x=CAS("x");
PRINT(x) → 0 //Why? recursivity?

LOCAL var1=CAS("x");
PRINT(var1) → x //Expected, usual practice

LOCAL x=CAS(CAS("x"));
PRINT(x) → x //Why???

I would like to know what this is due to and if there will be any correction in this regard.