The idea of merit isn't terrible in the abstract - it's basically the idea that the person with the most aptitude for a specific thing should be one doing it, particularly instead of the most connected, most high born, etc.

That the connected and high born should turn this to their advantage by creating measures of merit that they buy just like indulgences is not surprising.

Because of this, I tend to think of merit as the ability of someone to make the most of their circumstances, as someone with a pedigree of indulgences is of suspect aptitude.