In the Mexican bail-out, creditors were paid back quickly in full by the rescue package, and this left a legacy of moral hazard. Whatever existing problems of moral hazard had existed before Mexico, these were substantially exacerbated by what was otherwise a very successful rescue.
Unless private sector creditors pay some price when things go wrong (either in terms of delayed repayment or some kind of “hair-cut”), then the market will not make the correct risk assessments, nor will capital be allocated in the right way and, most serious of all, we will get repeats of these enormous and disruptive influxes of capital, with the resulting problems.