Socialism has not worked in the world because true socialism has not existed. In current socialisms, some people are more "equal" than others.
Ah, the old "it will work this time" notion or "well, all those utter failures weren't really socialism's fault (while I blame every ill on capitalism)".
The reality is that socialism always fails because the idealistic ideology doesn't take into account human motivations and fails to control them (actually provides for systems of gross injustice and unfairness) whereas capitalism tends to align with them and as long as they are controlled can benefit from them and channel them into benefits for all.
There are a number of reasons that socialism fails but it boils down to stopping the 10-20% of people responsible for output in most systems from being motivated to create and produce.
The massive improvements in world conditions in the last 200 years are down to capitalism. It delivers results unlike any socialist system ever. Period. People just have to get 'over' the fact that for the better system to exist, some people will become wealthier than others. But the notion that the 1% or 10% is fixed is wrong - there is actually a lot of churn of wealth, more than many imagine, with a much larger proportion spending some of their life in the top tier and wealth not always sustained across generations.
Socialism typically produces misery and death. That's not hyperbole, it really does - more people have died in Venezuela than have been killed in Syria for instance. Does that get reported by any socialist leaning news groups? Of course not ... it's endless wall-to-wall pro-socialist propaganda and chearleading.
Now you have a failed political movement doing the typical trick - promising free everything! Healthcare, education, even housing - it can and should all be free! And the people promising everything have as little understanding of basic economics as you imagine it is possible to have.
It's a path to ruin. First economic, and then social. For anyone unhappy at gun ownership, this is a prime example of why no one in their right mind would give up their weapons when there is a party spewing nonsense like this because one day they may well be needed.
And you also seem to mix up socialism and liberalism. The most liberal countries are capitalist because they see people as potential customers. Socialism is usually all about controlling people and seeing them as resources to be used by the state system, not individuals who want to live their life however they want.
The remit of government should be to ensure markets operate fairly, to provide law and order and defence and to protect against the damage that a focus on short-term profits alone could do (e.g. environmental) and to invest in shared infrastructure (roads, rail etc...). On the whole, more government and more state control of things like education creates worse results and opportunities for people to enrich themselves from the bureaucracy - and like most organizations, there is then a tendency for the government to protect itself so it becomes harder to root out such things.
Elect a leftist government and you get back-door socialism - an ever expanding 'welfare state' to create an underclass of voters, open borders to import more people looking for handouts to bulk up the system and the votes to perpetuate it and falling economies while the people at the top enrich themselves.
No thank you.
It's more liberal and caring for people to want a system that works for all, not just a very select few.