Learning something new is usually a walk in the park(not literally) when there's interest. But even in the presence of interest, nothing is very easy to assimlate and maybe, that's exactly why it's being taught. It takes some mental and physical preparedness. Which is like to describe by the words "determination" and "self-effort."
Personally,.I would not accept to join any field where I have no interest. Because then, I may spend all the time there learning absolutely nothing. But say I enroll to learn an activity of choice, in very little time, I'd gain some mastery. I guess it's just how things work generally and it's even prevalent amongst young children.

Throughout my years in high school, I excelled at my academics. As an A-list student. But one subject I didn't quite get what Physics. Truth is, I managed to always pass it in assessments and exams, but I never got a hang of it. Till this moment, I can not recall one aspect I learned well at school. I leveraged on my knowledge of other subjects and just accepted that Physics was tough and not for me.
Fast forward to the period I was preparing to take the examination that would get me into college. My big brother took it upon himself to tutor me. And finding that I was no good even at the littlest and most basic of Physics questions, he disregarded other subjects to major here. But having registered the "it's too hard and I can't learn it" thought in my head, it was very difficult. Sometimes, I'd try to evade the class. He taught and taught me from the very foundation(even down to basic maths) yet i couldn't get anything in.
I'd listen to hus explanations, watch him solve the problems, yet nothing was sinking in. I recall having to solve a simple question that had just been taught to me for minutes without avail. I recall been given a question over and over again yet I couldn't do nothing. Ah, physics showed me shege. It was exhausting. Nothing was entering and I disliked the subject very much.
But I(read as my bro) didn't stop. He'd explain one thing over and again before I'd even see the light in it. Physics gave me chills.
And my bro pissed me off even if he was patient throughout the time. He's better at teaching than I am, by the way.
But overtime, because I had come to the knowledge that I couldn't run from it(or maybe it came to the knowledge that it couldn't run from me), my lessons began yielding result and I started to gain interest.
Now, today, ask me of the subject I love and have better knowledge about and I'd tell you that it's Physics.
And then teaching.
This one was easy for me. Not because I was already a certified teacher. No. But because I loved the activity. I started holding lessons for kids my age and younger when I was very little. It's an area I thrive well in. What I had to learn though was how's to deal with the needs and peculiarity of each child. By the way, this is where conflict arises for some other educators but because I was invested in giving and getting out only the best, I learned that and much more. The sector goes far beyond having vast knowledge of the maths and subjects been taught. Fostering relationships, handling the environment, noting differences, and generally the management of the scenes are part of the job. I hadn't known all those in the beginning but in no time, I was an all-round pro. No stress.
For me, I think interest had a major role to play.
Thanks for gracing this post.
Greetings!