I did always feel that
Iron Fist had more than a hint of Popeye about him; in the sense that Popeye would always wait until he'd been battered from pillar to post before it occurred to him to eat his spinach. Likewise, Iron Fist always seemed to wait until he'd been half killed before he thought to use the thing that actually gave him his name.
As for his iron fist, it was basically him thinking about his hand so much that it practically caught fire.
I'm not sure that the ability to almost set your own body parts on fire is a good thing but it did at least enable him to beat up people who'd spent twenty pages stomping all over him like he had all the fighting skills of a dead sheep.
And, of course, it all started in
Marvel Premiere #15, in which we first meet our martial arts maestro as he seeks to pass some test or other by bashing up various people, in a room, in order to gain the approval of a man in a mysterious hood.
I do generally feel that doing anything purely to gain the approval of a man in a hood is rarely likely to lead to a happy outcome but that's probably my natural scepticism showing through.
Sandwiched in among all this non-stop action is a flashback sequence in which we discover that he's Danny Rand whose parents had dragged him off in search of Marvel's answer to Shangri-La when he was a child and, when it had all gone wrong, he'd found himself taken in by the locals and taught to be a human killing machine.
Anyway, the tale climaxes with him beating up a seemingly unstoppable robot as we're promised even more thrills and spills next issue.
Exactly where the rulers of a lost city in the Himalayas got a robot from is anyone's guess but it was certainly an action-packed debut and a lot less thoughtful than we were getting from
Shang-Chi at the time.
A lack of inner composure wasn't the only thing that set Iron Fist apart from Shang-Chi. While Shang-Chi's captions were in the First Person, Iron Fist's were in the not-often-used Second Person, which means we got a lot of, "You are Iron Fist. You are angry. You hit him with your feet." Quite who this person was who was doing the narration, and why they felt a need to keep telling him things he already knew, was never clear.

It has to be said his origin does bear noticeable similarities to that of television's
The Champions who were likewise incapacitated in the Himalayas before being rescued by locals who taught them to make the maximum possible use of their natural abilities before unleashing them once more upon the world. Whether this resemblance was coincidental or not, I have no idea.
Somehow, you never got the feeling that Iron Fist was as good at the martial arts as Shang-Chi, judging by the fact that the latter always managed to defeat his foes without having to have an iron fist to fall back on.
Then again, if Iron Fist had only had the sense to use his iron fist at the start of a fight, it wouldn't have mattered.