Why did Luffy in One Piece make all his partners want to follow him?

Lufei is "stupid", and an overly intelligent leader will give the team invisible pressure, which is not conducive to the free development of the team. In the end, there are only smart people and really stupid people left in the team. Looking at the top team of One Piece, Roger, white beard, red hair and even Aunt Cardo are not so smart. While they have their own minds and visions, they may be a little "stupid" in other aspects. The same is true for Luffy. It is very comfortable to let their players develop according to their own characteristics. The counterexample is Captain Crowe's black cat pirate.

Luffy is "one track-minded", and the things he believes remain the same. I don't know if you have noticed, but Luffy didn't listen to Nojiko talking about Nami's past. That is to say, for Luffy, there is no doubt that Nami is his sailor. At present, Nami told him to "get out" and he went for a walk. Nami asked him for help, and he naturally made moves. Don't need any other reasons. Nami's past is for our audience, not for Luffy. Luffy's recognition of Luffy has always been unwavering. Robin Brooke, Nami, and now Shan Zhi. "I treat people sincerely and never give up", so the members of the straw hat group are naturally willing to follow Luffy.

Of course, Luffy has other advantages. But I think these two points are the most important.