Why did the Nazis persecute certain groups?

Also the same answer can be given to "Did the Nazis only persecute the Jews?".
Hitler believed in the Darwin theory of evolution that stronger people live and weaker die.
Hitler felt that Aryans were the master race and often blamed other groups for losing the war.
The unhealthy, disabled, and tramps were seen as worthless and expensive.
Alcoholics, prostitutes etc were seen as undesirables.
Hitler didn't like gypsies and they too were persecuted as they didn't work.
Jews - got good jobs, Germans were jealous, successful commerce, not pure German were all reasons why Hitler persecuted Jews.