Yeah, I do admire the Democratic Socialists of Northern European countries. Those countries are rated as the happiest places to live in the world, and do seem to try to come to a balance between capitalism ans socialism.

Agreed

The failure(s) in socialism was in trying to apply the solution Marx proposed in the way he proposed it. Northern European countries with democratic socialism have found an alternative way to achieve socialism goals, and they are rated as the happiest places to live on earth.

The primary problem withe Marx's proposed solution is the idea of revolution, which results in a dramatic change in how economies work. The only way to force such rapid change is with concentrated power by one or just a few persons, and as the saying goes "power corrupts and absolute power corrupts absolutely." Also, persons who seek dictatorial powers almost never give up any power voluntarily, which is why most socialist revolutions end up in some form of totalitarian government.

In Northern European countries rather than having a revolution and trying to impose instant change, they made gradual changes over time to improve things for all of their citizens. Thus, the economy wasn't disrupted, and leaders were elected and held accountable for their actions, which is why it worked and is still working very well.

As I originally said, the problem was not in Merx's identification of the problems and excesses of capitalism, but it was his proposed solution that was problematic and fallacious.