Unfortunately in the promise lies the problem - it depends on the promiser's goodwill. This is why there's a need for laws. So you don't rely on the promise of a politician. After all, it's a contradictory nature; Limited terms, and even Democracy entirely, were created because you can't trust people in power for long. Power corrupts. It's quite possible he really meant that promise at the time (אשרי המאמין) but then he slipped when the time came.
I can't really blame the current generation of politicians. The system molds them to be what they are today. It rewards them to act like that, and punishes them when they don't. I can only blame the first generation of politicians who allowed legal voids to exist and be exploited, and the people who won't demand a change.