Anarchist philosopher and writer Pyotr Kropotkin wrote this amazing article called "Are we good enough" and I'm going to copy paste part of it here because it's really relevant to your point about preventing bad people from taking over

Men are not good enough for Communism, but are they good enough for Capitalism? If all men were good-hearted, kind, and just, they would never exploit one another, although possessing the means of doing so. With such men the private ownership of capital would be no danger. The capitalist would hasten to share his profits with the workers, and the best-remunerated workers with those suffering from occasional causes. If men were provident they would not produce velvet and articles of luxury while food is wanted in cottages: they would not build palaces as long as there are slums.

If men had a deeply developed feeling of equity they would not oppress other men. Politicians would not cheat their electors; Parliament would not be a chattering and cheating box, and Charles Warren’s policemen would refuse to bludgeon the Trafalgar Square talkers and listeners. And if men were gallant, self-respecting, and less egotistic, even a bad capitalist would not be a danger; the workers would have soon reduced him to the role of a simple comrade-manager. Even a King would not be dangerous, because the people would merely consider him as a fellow unable to do better work, and therefore entrusted with signing some stupid papers sent out to other cranks calling themselves Kings.

But men are not those free-minded, independent, provident, loving, and compassionate fellows which we should like to see them. And precisely, therefore, they must not continue living under the present system which permits them to oppress and exploit one another

To answer the question you presented at the end of your comment, Kropotkin says no. There is no way to prevent this and thus we must destroy the positions of power to stop men from using it to oppress others.

Full link to Are We Good Enough

https://theanarchistlibrary.org/library/petr-kropotkin-are-we-good-enough

And in video format for those who prefer to listen instead of read

https://youtube.com/watch?v=t2Al-ivn074&feature=share8