Now the last mentioned condition is quite real. Its effectiveness is guaranteed by the very insufficiency of capitalist reforms. But the conclusion drawn from it could only be true if it were possible to construct an unbroken chain of augmented reforms leading from the capitalism of today to socialism. This is, of course, sheer fantasy. In accordance with the nature of things as they are the chain breaks quickly, and the paths that the supposed forward movement can take from the point on are many and varied.

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"The present State is first of all an organization of the ruling capitalist class. It assumes functions in the interest of social development only to the degree that these interests and social development coincide with the interests of the dominant class."

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"The fundamental relations of the domination of the capitalist class cannot be transformed by means of legislative reforms, on the basis of capitalist society, because these relations have not been introduced by bourgeois laws, nor have they received the form of such laws."

&c.

Rosa's Reform or Revolution is a critique of Eduard Bernstein's reformist argument, and goes into detail about how reform is not the solution. It basically boils down to without owning the system, reforms cannot be guaranteed to last and reforms on their own cannot change the system to one we need.