In my experience, most groups that claim to be an ideology just end up using a harmful, wildly distorted version of it.

This will be on my wall when I've got my printer working. (So many cables!)

Examples:

• The "Union of Soviet Socialist Republics", or "Soviet Union" – an authoritarian malevolent (or at least ethically questionable) dictatorship where virtually everything was owned, not by the state, but by the dictator. Originally derived from Marxism, adapted by a minor political party to fit a pre-Industrial Revolution society, adapted by the minority faction of that party to be a rebellion of them, not of the masses, adapted by Lenin to not cause the country to collapse, adapted again by Lenin to not cause the country to collapse by force (with some Secret Police becoming a little more obvious), adapted again by Lenin because force wasn't working and the country was still collapsing, adapted by Stalin repeatedly to make himself into a god-like benevolent figure at the expense of literally everything. They replaced an incredibly incompetent benevolent-but-out-of-touch king with a neutral dictator, who then died and was replaced by an in-touch incompetent malevolent dictator.
• … all of my other examples are current events, which I don't want to comment on.