Raul Gallegos argues that the 2014 Social Progress Index proves that left wing governments do more poorly than governments that lean more to the right.
The index itself, though, shows a more complicated picture. Gallegos doesn't mention Colombia, for example, which has had governments that Gallegos considers optimal yet still is worse off than Ecuador and Argentina, which have leaders with "useless ideologies." Guatemala, which has been governed almost exclusively by the right, is really low as well.
And thinking of those useless ideologies, he focuses on Bolivia and Nicaragua:
The problem with Latin American populists such as Venezuela’s Maduro or Nicaraguan President Daniel Ortega isn't so much their commitment to useless ideologies; it’s that their failed economic tinkering is mostly aimed at keeping them in power.
The thing is, these are two very poor countries that score low no matter who is in power. Both had years of right wing governments that didn't improve anything either.
So maybe, just maybe, these outcomes are not due directly to ideology of the current government but rather are the result of many factors (of which ideology is just one), some of which have deep historical roots.