>I can cook, but to me it's like changing my oil or cleaning my apartment. Some people love to make a face and go "you don't cook?!?!?!"
It's a tradeoff of time and money in most cases.
For oil changes, for instance, if I live in a place with a garage and I have my own tools, it's faster for me to do it myself than to pay someone else to do it: for the latter, I have to schedule an appointment, take time off from work (using PTO, or coming in late/leaving early), drive to the place, sit and wait around while they do it, and then worry that they screwed it up (which is pretty common). Plus the prices are much, much cheaper if I buy the supplies myself instead of paying inflated prices at a shop. Of course, if I live in a place without a garage or other place to do it myself, then I might not have much choice.
Cleaning my apartment: I'm not sure how this is helpful to outsource. Perhaps if you hire a small crew, it'll be done quite a bit faster than you can do it yourself, but you still have to take time off from work (or your weekend), then sit there and oversee these people to make sure they're not stealing your stuff (very common), while they do the cleaning. And having strangers walking around your home is, to me at least, very uncomfortable.
With cooking, you have to consider the time needed for you to go to the restaurant and pick up the order (probably waiting when you're there, unless the food is sitting and getting cold) and drive home. Or, you can pay for delivery, but this costs extra. Now, if you live in a very dense city where the restaurant is right around the corner, or delivery is super-cheap (because it's right across the street), then this might not be much of a factor, but in much of America it is. It takes me about 15 minutes or so to cook dinner usually; it would take me much more time than that to go someplace else to get take-out, and by the time I get home it'll be cold, and it'll cost 5-10x as much as making it myself. Plus you have to worry about getting sick due to cooks not washing their hands or not storing or preparing food properly, which is very very common in America. If I lived in someplace like Singapore (as referenced in a sister comment here), I'd probably get food on the way home frequently, but not in America.