how does 何の部活もやってこなかったもんね mean you've never been in any kind of club

Question

I was watching the first episode of the anime k-on and I saw this

こうやってニートが出来上がっていくのね、何の部活もやってこなかったもんね

the subs said that the sentence meant

that's how people become neets

I'm confused by this firstly why use いく here

こうやってニートが出来上がっていくのね

doesn't the 出来上がる already mean to complete or become

and my other confusion

何の部活もやってこなかったもんね

I don't understand why this means you haven't been in any clubs with my current understanding I would say its

what clubs have you not done

or

what clubs didn't you do

which is wrong but I don't get why what am i missing

Answer 1

いく in 出来上がっていく describes a process of change that goes on into the future. こうやってニートが出来上がるのね is also fine. いく adds a nuance that this process, of neets being created like that, will continue. She may have in mind other people like the person she is talking to becoming neets through a similar process.

部活をする or 部活をやる refers to the act of engaging in some activity as a member of a club at school. 部活 here is the object of the verb する or やる.

You should understand 何の部活もやらない the same way you would other sentences with a question word like 何 and も, such as 何も食べない.

何の部活もやってこなかった describes a process that has led to the current state in this context. So the translation seems correct.