why the vast majority of examples of android declares the return variable as final in methods like findViewById(id)? For example:

```
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_list_enc_disp);

    final ListView listViewEncDisp = (ListView) findViewById(R.id.listViewEncDisp);
    listViewEncDisp.setOnItemClickListener(this);
}

```

I know that a final variable can not be assigned again, however do not understand why you need this good habit.
Thanks in advance