Nothing.

While I realize that this is poor answer for /r/askhistorians, but your question is victim blaming. Nazi's and Germans in general bought into a paranoid, racist worldview that scapegoated and blamed Jewish people for their wrongs. Jews people did absolutely nothing to merit any harm.

Jews (and I am proudly one of them) have pissed off the majority of peoples who they have interacted with mostly because we're very resilient to assimilation. Remember that modern ethnicities were really only formed on strong grounds no earlier than the 18th century, and much of ethnicity before this was incredibly fluid. There's a reason there are no modern Thebans, Thracians, Dacians, Celts, goths, etc. today and that's because these groups have mostly been assimilated into other cultures. At times throughout history, there have been calls for the revival of an ethnic group on (incorrect) historical interpretations of modern association with these ancient peoples - see the Romanian connection to the ancient Dacians under Ceausescu.

My point with all of this is that Jews, unique from almost any other group, managed to both carve out an ethnicity AND preserve it for thousands of years, despite most of that time not even having a homeland and simply existing in the homelands of other groups (many of which themselves have ceased to exist). The resilience of Jews as an ethnic group comes from their refusal to assimilate into a dominant culture in countless different aspects of society. As a result, it's incredibly easy to "other" Jews and make them seem as outsiders in a society they may have lived in for centuries. Much of that comes from our own stubbornness to resist assimilation, but a large portion of that is also thrust upon us. To the Germans (not just the Nazis, but also for hundreds of years before), it was really easy to hate us simply because we refused to be German. When things when wrong in society, like famines, plagues, social unrest, whatever, it was far easier to blame the scary outsiders than it was to actually address the real problems from within.