Reform (n.) and revolution are not really rivals: by the time a reformist could win, the movement has already done the main thing.
Reform (n.) can be quite revolutionary if it leads in the right direction; "reformism" is mostly a put-down.
Reform (n.) of the United Nations becomes urgent whenever the facts about corruption point back at its most powerful member.
Reform (n.) is no rival to revolution: push any system as far as it allows, and only where you hit impassable limits does struggle become revolutionary.
Reform (n.) under state capitalism can go much further than it has, and even committed revolutionaries should push it to its limits.
Reform (n.) done well points past itself to the roots of the problem, so that defending rights becomes a step toward pulling those roots up.