Can't re-instantiate/respawn object I've destroyed in Unity3D

Question

I've 2 scripts. 1 makes objects and the other destroys them.

I first press OnSave button which runs script #1 and creates my objects. (there's more than one, although here in the script just shows one, I shortened for the sake of question)

then I press OnReset button which destroys created objects/prefabs. But when I press OnSave again, it doesn't recreated objects.

These 2 scripts are attached to 2 different gameObjects

here's what I have:

script #1:

public GameObject go;
public static volatile List<GameObject> prefab = new List<GameObject>();


public class OnSave : MonoBehaviour
{
public void Start2()
{
                var newObj = Instantiate(go);
                newObj.transform.parent = GameObject.Find("MOOSE").transform;
                newObj.GetComponent<Renderer>().material.color = Color.green;
                newObj.transform.localPosition = new Vector3(1.0,1.0,1.0)
                prefab.Add(newObj);


}
}

script #2

public class OnReset: MonoBehaviour
{
foreach (GameObject obj in prefab)
{
Destroy(obj);
}
}

I'm using the latest version of Unity. I have to destroy these objects and recreate them

Answer 1

You need a prefab to be able to reinstantiate the object, but the operation of destroying and reinstantiating is heavy, so normally you use a pooling manager of sort like https://www.assetstore.unity3d.com/en/#!/content/47242 (disclaimer: I'm the author of this one) or https://www.assetstore.unity3d.com/en/#!/content/23931 .

Here's the official Unity totorial about pooling objects: https://unity3d.com/learn/tutorials/topics/scripting/object-pooling