Iron-Fist was a run-of-the-mill crook with a flair for technology he couldn't control. In other words, his genius outraced his common sense. Enter the Web, who fearlessly will always confront any ill-tempered individual (save his wife during one of her mood swings), regardless of their armaments.
In the end, each Iron man faced defeat by different means. For Iron-Arms, it was simply that his powerpack was overexerted when facing the atomic avenger, leading to this one-trick pony konking out for good. For Iron-Fist, it was due to the shamefulness of having an adversary pollycoddle to his wife... seriously that is what happened back in the silver age days of Mighty Comics ... causing the rogue to rethink his own priorities! Neither proved a fitting tribute to the enduring legacy of their Marvelous inspiration!