In my experience, at first managing is always harder than doing it yourself, because you're usually put in charge of managing people who do what you used to do.

Have you ever been in a situation where you've had to do something at work, but you were hamstrung by your tools or timelines? Like, oh man this would be way easier in Python but you are only approved for MS office, so you have to struggle through some VBA. Or man, I could whip this together super fast in Ruby but for some reason this has to be in plain JavaScript. Or maybe you could make this really well, but not in the two day turnaround they need. All that is frustrating, but you usually find a way to perform given these imperfect scenarios.

Now, imagine VBA has feelings. You can't even really complain about VBA, because it's not malicious. It's just bad at its job. So now instead of quickly coding a workaround in a new language (but you learn fast so not the end of the world), you have to help someone get there and do it on their own. And you can't just do it for them because you have 4 VBAs. Oh, and by the way, JavaScript is malicious. It's actively trying to avoid work, or maybe trying to make VBA look bad. So now you have to convince JavaScript that it's in its best interest to work. Sometimes its a carrot, sometimes a stick, but you're responsible for getting functionality out, and it's more functionality than you could possibly create on your own.

That's what managing people is like. A deep desire to do it yourself because it will be better and faster, but you don't have time, and also you need these people to be better. So you have to learn to teach instead of do, and support emotionally and intellectually and motivate instead of just bitching to your manager when someone else isn't getting their work done and it's affecting your work - now you're responsible for getting their work to be good. It's really hard, and some people who were amazing achievers and doers can't hack it when they have to help other people achieve and do. It's why you have so many bad manager stories. The skillsets are nearly completely different.

The nice part though is when you get good enough at managing that you start managing people that do things you can't do, or do things better than you ever could. Suddenly there's some whiz kid straight out of college who knows more about data science from their degree than you did your whole career actuallydoing it, and all they really need help with is applying it. Then you start helping with vision and the "why" of things. "Yes, you could do it that way, but remember our actual end goal is X, so that's all we really care about." Or you help people work together to make a cohesive whole. That's when managing gets really rewarding. It can still be harder than doing, or it might be easier if you're a big picture thinker, but it gets different eventually.