The thing that I like cubing is that there are so many aspects to it. The aspect that attracts me to cubing the most is probably the aspect of always having something to improve on. Imagine you were grinding for 2 months and finally became sub 20 on 3x3. You will have the feeling of relief and happiness from reaching your goal, but that doesn't mean you are done there. When you meet your goal, all that means is that you need a new goal, so you keep pushing to sub 15, sub 10, sub 8, and maybe even sub 5. Then, years later, when you look back at all your progress you realize how much improvement you made, from being a 5-10 minute solver, to being maybe the best in the world.
Another aspect that I love about cubing is the never ending list of things to learn. I really started getting into cube theory, FMC, and advanced techniques after looking at clock. At first the puzzle seemed really simple, just solve one cross, flip, and solve the rest. But then I learned about corner skips, psuedo skips, then simultaneous turns, no-flip methods, and then I created my own no flip method and optimized another. I kept learning so many techniques and became so familiar with the puzzle, and it was so fun! I know that most people don't like clock because it is a weird puzzle to have in the WCA but I really love how much you can keep learning about it. My favorite events are probably FMC, 3x3, Pyraminx, Square-1, and Megaminx. Pyraminx I just like because I am good at it, but the others are so similar to clock in that there is so much to learn and that it almost feels endless. Applying those techniques in solves is even better; the feeling of getting a ZBLL or PBL you know, taking advantage of psuedo corner skips, having a super efficient F2L or S2L, canceling a lot of moves in an insertion under time pressure. That is so rewarding and it just brings so much joy to me.