Why are a lot of players getting stuck at ratings 1200-1400?

Just wanna know.    ._.

Just start practice more !!!

Seems legit

Puzzles are also a good way to help recognize patterns. They also help you find better moves and checkmates. 

eeeh

Because they don't care for material.

Chess is not an easy game. After a certain point, you need to work at it. And you only work at it if you really like the game.

because 1200-1400 is a comfortable rating rage

1200 ~ 1400 is the level where you stop blundering your pieces. That is really the first hurdle.  

1400 ~ 1800 is when you know the theory and can think far enough ahead that you stop making mistakes.

Once you get to 2000+. moves that would be considered, "good" for a 1200 ~ 1400 would be your blunders. 

And each step is a lot of work. A lot of people like chess, but they don't want to put in the hours and hours to get better. 

" A lot of people like chess, but they don't want to put in the hours and hours to get better. "

Very true. Luckily, chess is a game that can be enjoyed both as a casual hobby, or a dedicated activity. It works both ways