Thank you for making it evident that you are presenting a straw man argument.
Which is a shame really.  This is a subject with some serious meaning.  Specifically how this kind of attitude gives politicians the incentive to lie, cheat and steal from their constituents.  If we choose to turn a blind eye to such blatant baloney of course they're going to weigh the risks of openly lying to their constituents over openly flip-flopping over an issue.
This is one of the rare occasions which shows the hypocrisy of the electorate.  We criticize politicians for flip-flopping or a lack of leadership when we cannot or simply refuse to admit to ourselves at election time that we want politicians to lie to us, to give us the pretty bottles of poison, rather than make sound decisions.