Why does steel man argument fail?

The most common reason steel man argument fails: Building a steel man that is actually a straw man wearing armor. This happens when you construct the opposing case using only the arguments you already know how to defeat, arranging them in a format that looks comprehensive but is still selected for refutability. The test is whether the other side would recognize your steel man as their actual position. If they would say 'that is not what I mean,' you have not steel-manned — you have decorated a straw man. The second failure mode is steel-manning as a performance rather than a practice. You go through the motions of considering the opposing view without allowing it to actually update your thinking. If you emerge from a steel-manning exercise with exactly the same position and exactly the same confidence, one of two things happened: either the opposing view genuinely has no merit (rare), or you did not let the exercise work.

The fix: Identify a contradiction you are currently holding — two beliefs that genuinely conflict. Choose the side you find less compelling. Now spend 15 minutes writing the strongest possible case for that side. Follow Rapoport's protocol: express that position so clearly and completely that someone who actually holds it would say, 'Yes, that is exactly what I mean — I wish I had put it that way.' List every piece of evidence that supports it. Identify the conditions under which it is clearly correct. Make it as persuasive as you can. When you are done, re-read your original position. Notice what changed. The contradiction has not disappeared — but your understanding of what makes it a real contradiction, rather than a fight between a strong argument and a weak caricature, has sharpened.

The underlying principle is straightforward: Before resolving a contradiction make the strongest possible case for each side.