mathematical optimization - Printing from the function to be minimized in FindMinimum

I know that there is an option EvaluationMonitor for various numerical computation and plotting functions.

But I am curious, why a simple Print statement in the function to be minimized does not print. Consider this example:

Clear[x, y, z];
f[{x_, y_, z_}] := (Print[

    "in function f called with these arguments: ", {x, y, z}]; 
   1 + x^2 + y^2 + z^2);
FindMinimum[f[{x, y, z}], {{x, 1}, {y, 22}, {z, -3}}]

in function f called with these arguments: {x,y,z}
{1., {x -> 0., y -> 0., z -> 0.}}

The result is OK. But I would have expected the first print output to have been

in function f called with these arguments: {1,22,-3}

Did I get that completely wrong? Or is FindMinimum using some fancy Compiled feature defeating the Print statement?

Comments

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