There are distinct requirements, goals, and levels in careers. You're just not in it yet, so you can't see it. Let me see if I can draw some analogies.

I have found that everyone feels differently about different types of jobs. Much like some people are cat people, some people are dog people, and some people are fine with cats and dogs living together, some people feel great working for start-ups where you are constantly burning it at both ends, some people are happiest working for a big established company with lots of policies and procedures, and some people like working for companies that are changing from being startups to being enterprises and have projects that fall into both camps. If you figure out what kind of person you are and you target companies that are of that type, you will probably be happy.

Your first job or two is probably going to suck. Much like the first couple of 100-series lecture courses at university, you will wonder why you are there, you will struggle to find meaning or joy in the material, and you will work hard simply to get through it. Your main goal here is to not screw up while you're figuring out what kind of person you are and where you fit in the management/technical tracks and in various teams. You should make sure that you stick your neck out as much as possible in these jobs without totally screwing the pooch. It's anxiety inducing and the sole purpose is to build your resume a little so you can level up. It's ok, it gets better.

Your third or fourth job, which you will get by finding out how to sell the experience and skills you gained in your first job or two and by networking with peers and generally being (or at least appearing to be) a smart person, will probably be joyful. Your focus here should be finding your boundaries and pushing them. You should try all kinds of weird new technologies and push the envelope. You should bend your brain until it breaks, have a beer, and bend it some more. You will probably create some amazing things, and you should keep track of them by frequently updating your resume. My only advice in this period is to take some time off frequently. It's exhilarating to be in this phase, but you can break yourself permanently. This is a marathon, even if you're sprinting all the time.

At your fifth job (or by about 35 years old) you might find your opinion about certain kinds of places and certain kinds of tasks and certain technologies solidifying. This is comparable to your third and fourth year of college. You know where you are, you know who you want to be, and now it's time to focus. This is where you will probably make your most important contributions... Even if you're me, working Ops, and your most important contribution is "Ah wouldn't do tha if ah wuz you."

After that period, you might find yourself in one or two places. But generally, at about age 40, you'll start to slow a little and might lose your ability to hop between companies. This is part of the focusing trend. Some people end up in management because they're technologically burnt out a bit. Some people double down on the technical track and go on to become graybeards. Some people quit and become hermits or police officers or consultants or bricklayers. This phase is comparable to grad school: instead of spending most of your time working with peers, you're spending most of your time teaching to those junior to you... And at the same time, you're still expected to be productive on your own. But you should have developed a plan for when you hit this phase, because grad school is not for everyone.

Hopefully that clears up a few things for you. It's not so much enjoying a job as it is enjoying what you get up and do every day, and changing what you do if you find you don't enjoy it.