Unfortunately, this is ahistorical. Failures of pre-Marx Socialists such as Robert Owen came from the idea that you could convince Capitalists to do the right thing if you proved it with logic and reason. Marx developed upon this and learned that Mode of Production largely determines what ideas are acceptable, rather than the Utopian idea that Socialists had to wait for a "Great Man" privy to universal truths to defeat everyone in some grand Marketplace of Ideas.
To expand: Robert Owen ran semi-Socialist company towns with large expansions in protections, lower working hours, and high rates of profit. When he took his model to the other bourgeoisie, he was cast out of high society and publicly humiliated. The problem with Utopians like Owen is that they became obsessed with imagining some grand model that needed to be thought of and started, that a perfect system existed and simply needed to be discovered in the mind of Great Men to exist in Reality.
There have, of course, been Capitalists who have made concessions, but these were won through conflict and struggle, not logic and reason. Instead, Marxists take the stance that development drives what's acceptable discourse, and that the next system in development emerges from the current system. Ie, Socialism is brought about from solving the contradictions within Capitalism, as made necessary from the progression of Capitalism. Monopolies and large armies of industrial workers equips the Proletariat with the Means and Knowledge necessary to bring about Socislism.
Engels writes about this in Socialism: Utopian and Scientific, I highly recommend this for those uninformed about Marxism. Engels is flowery in prose, but it's an essay that takes roughly an hour to get through.
