Say your comic needs a robot but you can't draw robots.
Or it needs a flashy outfit but you're not a cloth designer.
Or there needs to be a castle but you know nothing about medieval buildings.
Or maybe you get some professional help to iron out some of your comic script's rough edges in a couple of important scenes?
Stuff like that.
Would you just plow through and try to do as best as you can, or you would rather leave stuff for people that actually know their stuff?
I think the "outsource that!" would be the better approach that would result in a better quality of your work (I myself commissioned outfit redesigns for my main cast because I can't design clothing for life, and logo design since apparently I suck at that too), but at the same time, it feels kinda slightly... wrong? Your comic becomes less... yours. There are elements in it now that you did not make, that you can't claim credit for, that feels a tiny bit like stealing even if you've paid for the work. Those outfit designs I've commissioned, for instance, I'm still wary of using them freely. Is it okay if I change them? Is it okay if I use their elements to make derivative designs? Is it honest to still say that the comic is made by "me"? I'm not talking about the legal copyright angle here, I do not particularly believe in the business side of the concept of IPs anyway, I mean more... ethical and moral sides, I guess?
I guess it's less of an issue in collaborative projects when multiple people provide their input in the comic-making from the beginning - you won't feel like it's your personal comic if you're just the script writer\illustrator\inker and there's at least one another that inputs an equal amount on effort into the comic.