I got really annoyed while watching youtube videos a while ago. I was just clicking on videos when I ended up on one comparing Taemin and Kai's dancing, and I got annoyed/pissed.

You can't compare them, really. They both are amazing dancers, the only difference being that Taemin didn't train for dancing, he just learned, where as Kai was trained in jazz dance and ballet, and later on hip hop and popping after joining SM. 

What annoys me the most though is when people say that Kai is more serious about dancing then Taemin is.

That's complete bull.

The video of Taemin dancing they tried to compare to Kai's was 10 times shorter, and it wasn't even serious. Taemin was on Maknae Rebellion, it was for fun, so he was smiling. Kai on the other hand, was dancing for a school performance. Of course Kai is going to be more serious about it in that video, it's for a performance. Taemin was just doing it for fun because they told him to dance to this song on the spot and he did. It's a variety show. Nothing is serious on a variety show.

Kai danced on Beatles Code 2 smiling, and you don't see people telling him he's not serious about dancing because of that.

If anything, during a SHINee performance, it's arguable that Taemin is the most serious. He'll be smiling and everything but once that music turns on he's completely into the music. SHINee likes to joke around during their performances, but you can see the difference in Taemin when he's really dancing compared to just joking around. You can't judge who's a better dancer based on a variety show cup and a serious performance. 

I'm not trying to say Taemin is better. Although I do like Taemin more, I'm not saying he's better than Kai at dancing, but I'm also not saying that Kai is better. They are both equally talented in what they do. Just because Taemin specializes on popping, doesn't mean he can't do other dances. He's danced salsa, as well as other dances, amazingly, and Kai has too. 

So no, you can't compare them. That's like asking, "Hey what's better? The spoon on the right? Or the spoon on the left?" when both spoons are exactly the same. 

So yes, I took my time to rant about this because it completely got on my nerves.