is it good practice to find game object at start if i already put it in inspector?

I need some advice.
while im writing my game script i just wondering if, is it good practice to find game object at start if i already put it in inspector? or it just wasting performance?
anyway, to not wasting so many performance i also using if before finding the game object at start.

i know it will not have too much different in performance. but the point i want to ask is, IS IT GOOD TO CONTINUE DOING LIKE THIS FOR NEXT WHEN I WRITING MY OTHER SCRIPT?

This is the script:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 using TMPro;
 
 public class UI_Character : MonoBehaviour
 {
     [Header("References")]
     public RawImage face;
     public TextMeshProUGUI levelTxt;
     public GameObject targetLocked;
     public GameObject frameA;
     public GameObject frameB;
     public GameObject shortInfo;
 
     [Header("Values")]
     public bool isLocked = false;
 
     private void Start()
     {
         checkReference();
     }
     private void Update()
     {
         //Use the the reference and do something
     }
 
     private void checkReference()
     {
         if (face == null)
         {
             face = transform.Find("Face_Mask").transform.Find("Face").GetComponent<RawImage>();
         }
         if (levelTxt == null)
         {
             levelTxt = transform.Find("Level_Text").GetComponent<TextMeshProUGUI>();
         }
         if (targetLocked == null)
         {
             targetLocked = transform.Find("TargetLocked").GetComponent<GameObject>();
         }
         if (frameA == null)
         {
             frameA = transform.Find("FrameA").GetComponent<GameObject>();
         }
         if (frameB == null)
         {
             frameB = transform.Find("FrameB").GetComponent<GameObject>();
         }
         if (shortInfo == null)
         {
             shortInfo = transform.Find("shortInfo").GetComponent<GameObject>();
         }
     }
     
 }