More end game

Now back to 9x9 boards.

static . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . .

Is this the end? It looks like white has a big win. However...

If you surround too large of an area, you run the risk of your opponent invading.

static . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . X . . . . X O . . . . . . . X O . . . . . . . X O . . . . . . . X O . . . . .

Here, it may be possible for black to make a live group inside white's territory.

While this may be difficult due to white's wall, white's territory would be drastically reduced if black is successful.

static . . . . . . . . . . . . . . . . . . . . X . . O . . . . . . . . . . . . . . X . . O . . . . . . . . . . . . . . X . . O . . . . . . . . . . . . . . . . . . . . .

Although it's far from the endgame, white has better prospects. Can you see why?