Update() problem?

I would like to ask for your help in clarifying the problem of my code :

void Update()
        Vector3 fwd = camera.transform.forward;
        Vector3 fwd1 = target1.forward;
        Vector3 fwd2 = target2.forward;
        if (Vector3.Dot(fwd1, fwd) == -1 && Vector3.Dot(fwd2, fwd) == -1)

            print("Both in front");


It supposes to print the message as long as the condition is met and every frame check the condition again?
Because when I insert the code into my rotating cubes, when I rotate them out of their forward directions, after rotating back to the original forward direction it does not print out the message anymore.

when working with floats, you want to use <= or >= instead of ==