Totally new, is there something wrong with this switch script for color changes?

I am still learning on my own with tutorials so any knowledge and direction would be amazing. The lesson I was going over was meant to teach using switches to change the color of an object. However, not$$anonymous$$ng I do makes the object respond as it did in the video. Is there somet$$anonymous$$ng my script is missing for that simple purpose? I am able to run it without being met with compiling errors or console problems so I am lost.

Here is what I have got, any suggestions?

using System.Collections; using System.Collections.Generic; using UnityEngine;

public class ColorChange : MonoBehaviour {

 public GameObject cube;
 private int _nextColor;
 // Start is called before the first frame update
 void Start()
 {
     _nextColor = 0;
 }

 // Update is called once per frame
 void Update()
 {
     if (Input.GetKeyDown(KeyCode.Alpha1))
     {
         _nextColor = 0;
     }

     if (Input.GetKeyDown(KeyCode.Alpha2))
     {
         _nextColor = 1;
     }

     if (Input.GetKeyDown(KeyCode.Alpha3))
     {
         _nextColor = 2;
     }

     if (Input.GetKeyDown(KeyCode.Alpha4))
     {
         _nextColor = 3;
     }

     switch (_nextColor)
     {
         case 0:
             cube.GetComponent<Renderer>().material.color = Color.blue;
             break;
         case 1:
             cube.GetComponent<Renderer>().material.color = Color.red;
             break;
         case 2:
             cube.GetComponent<Renderer>().material.color = Color.green;
             break;
         case 3:
             cube.GetComponent<Renderer>().material.color = Color.black;
             break;
            
     }
 }

}