Sometimes coroutine doesn't execute after yield return new WaitForSeconds()

Questions & Answers
1

I have written a coroutine that handles the texture change.
Here is the coroutine

public static Coroutine Init_textureChange;

public void TriggerTextureChange(Renderer [] renderers, Texture texture)
    {
        if (Init_textureChange != null)
        {
            Debug.Log("Coroutine is: "+Init_textureChange);
            StopCoroutine(Init_textureChange);
            //Set2DefaultTexture(renderers);
        }      
        Init_textureChange = StartCoroutine(InitTextureChange(renderers, texture));
    }

private IEnumerator InitTextureChange(Renderer[] renderers, Texture texture)
    {
        float duration = 0.2f;
        Debug.Log("Init texture change");
        //Applying damage texture.
        foreach(Renderer renderer in renderers)
        {
            Debug.Log("Count:" + count);
            renderer.material.SetTexture("_Detail", texture);
            //renderer.material.SetColor("_Color", Color.red);
        }

        Debug.Log("Texture applied");
        yield return new WaitForSeconds(duration);

        
        //Reset the texture to normal 
        foreach (Renderer renderer in renderers)
        {
            Debug.Log("Count:" + count);
            renderer.material.SetTexture("_Detail", null);
            //renderer.material.SetColor("_Color", Color.white);
        }

        Debug.Log("Texture set to normal");

    }

But sometimes coroutine doesn’t execute completely and stops before “yield” line.

2

I believe you have to return null every time you finish the loop inside IEnumerator to return the value

 foreach(Renderer renderer in renderers)
 {
     Debug.Log("Count:" + count);
     renderer.material.SetTexture("_Detail", texture);
     //renderer.material.SetColor("_Color", Color.red);
     yield return null;
 }

also in the second foreach loop

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