swich case not working properly

Hi guys, sorry for the long-ish code but i just decided to copy the entire method. In my for loop, as long as (i < worldSize), a world object will be instantiated, where index 0 is a sea tile and index 1 is a land tile. In other words this creates a small ocean world with an island. The problem i am facing is in my else if code, my switch case instantiates a large island when it should only instantiate a 1 tile island. This island should only be instantiated when (i = islandPosition), whereby island position is a random # in my worldSize.

  void createWorld(){
          int i;
         for(i = 0; i < worldSize; i++){
             linkPosition = GameObject.FindWithTag("seaLink").transform;
            // removeTag();
             if(i != islandPosition){
             //instantiate sea
             Instantiate(worldObjects[0],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
            
             }
        else if (i == islandPosition){
             //float islandSize = Random.Range(1,4);
             int islandSize = 1;
             switch (islandSize){
              case 1: 
              Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Debug.Log("island 1 tile");
              break;
              case 2:
              Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Debug.Log("island 2 tile");
              break;
              case 3:
              Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Debug.Log("island 3 tile");
              break;
              case 4:
               Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Debug.Log("island 4 tile");
              break;
              default:
               Instantiate(worldObjects[0],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Debug.Log("island default tile");
              break;
 
             }

          Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
             Instantiate(worldObjects[1],linkPosition.position,Quaternion.identity);
             linkPosition.position += new Vector3(perfectTileLink,0,1);
 
         }
       
         
         }
       
         Instantiate(worldObjects[2],linkPosition.position += new Vector3(-20,8,0),Quaternion.identity);
         //Instantiating portal;
         int fishingSpots = Random.Range(0,3);
         for(int f = 0; f <= fishingSpots; f++){
      waterTiles = GameObject.FindGameObjectsWithTag("sea");
 //     Debug.Log("Number of waterTiles = "+waterTiles.Length);
      int chosenTile = Random.Range(0,waterTiles.Length);
      Instantiate(seaMiniGame[0],new Vector3(waterTiles[chosenTile].transform.position.x,-4,0),Quaternion.identity);
 
      for(int number = 0; number <= smallIslands; number++ ){
          Instantiate(smallIsland[Random.Range(0,smallIsland.Length)],
          waterTiles[Random.Range(0,waterTiles.Length)].transform.position,Quaternion.identity);
      }
         }
     }