If you dogmatically look to other people's theories for justification for your beliefs you just have a religion. I read a book of theory every couple of months to check for new ideas that I may want to incorporate into my own beliefs. Anarchism is about free association and the abolition of involuntary hierarchies (among many other things). Wanting the person who has built five houses to organize and guide the group though building their first house is not contrary to any of that. You can always jump on your bike and leave or talk to the rest of the group and see if everyone agrees that the person organizing and guiding needs to leave because they are being a dick or making bad decisions/recommendations. With a boss, supervisor, government official there would be many different consequences and forms of coercion invoked due to the refusal to obey an order or law.

Also there is a difference between the colloquial use of a word and its actual definition, I suspect you are defining leader/leadership in the colloquial way instead of by its actual definition. The definition of leadership does not involve coercion at all, in fact if you have to coerce or force obedience you are by definition not a leader you would be a "superior", official, or boss.

What were Durruti or Makhno if not leaders? Or Montseny or Garcia Oliver?