Well, the second repeating mission does explicitly state "When you have obtained at least 4 components, you can [do stuff with em]" and "This mission is never finished", and when you get 5 components you even get a little pop-up saying now you can craft with em! I don't know what more explanation you could want.
But for some reason the first repeating mission - the one players are likely to take first - does not... :/
But for some reason the first repeating mission - the one players are likely to take first - does not... :/