Question Objects not getting destroyed

I destroy objects with certain tag except one, but they're not getting destroyed.

Code (CSharp):

1. smieci = GameObject.FindGameObjectsWithTag("Respawn");
2.         Debug.Log("pl " + smieci.Length);
3.         for (int i = 0; i < smieci.Length; i++) { smieci[i].GetComponent<RuchBlok>().dest();  }
4.         if (this.GetComponent<Timer>().gracz() == 1)
5.         {
6.             if (this.GetComponent<SzachMatPat>().szach(krow, 0, 1))
7.             {
8.                 this.GetComponent<SzachMatPat>().matpat(0);
9.             }
10.         }

Code (CSharp):

1. public bool matpat(int czarny)
2.     {
3.         if (Gra.GetComponent<Timer>().gracz() > 0)
4.         {
5.             GameObject[] smiec = GameObject.FindGameObjectsWithTag("Respawn");
6.             Debug.Log("mp " + smiec.Length);
7.             GameObject[] piony = GameObject.FindGameObjectsWithTag("Player");
8.         }
9.     }

Code (CSharp):

1. public void dest()
2.     {
3.         if (transform.position.x < 10)
4.         {
5.             Debug.Log("dest");
6.             Destroy(gameObject);
7.         }
8.     }

In the console i get:
pl 5 (5 objects exist)
dest
dest
dest
dest (destroying the four objects)
mp 5 (still 5 objects remaining)

I can't find where I get it wrong.