In this shape, basic instinct may inspire one to play White a. Yet, it will often be better to jump to b because of the hanging connection at .
(11 at ). In this diagram, White cuts Black to pieces.
Although this may not work immediately, the black position now contains much bad aji.
If White plays according to her underdeveloped instincts, she is letting Black get ahead all the time and build up nice potential - sometimes even definite - territory.