Machiavelli claimed that those who come to power by crime kill fellow citizens and betray friends. They are “treacherous, pitiless, and irreligious.” Thus, those who commit criminal acts can achieve power, but never glory.
In The Prince: Chapter 8, Machiavelli describes Agathocles of Sicily who became the King of Syracuse. He was the son of a potter, and from start to finish lived a wicked life. This King came to power not because he had help from above, but because he struggled from the bottom up. In doing so he obtained a monopoly on power and then held on to that power though less than moral tactics.
Machiavelli argued that a prince cannot achieve success without sometimes resorting to ruthlessness. He did not propose ruthlessness for its own sake, but rather indicates the necessity of ruthlessness in leadership. Machiavelli contends that by such means, one can acquire power, but never glory as “to massacre one’s fellow citizens, to betray one’s friends, to break ones word, to be without mercy, and without religion” is not to be called virtue so one cannot attain ultimate glory through the acquisition of power.