Off course there are general principles that apply to endgames. But mere intuition brings you most of the time nowhere. You have to calculate very careful.

See this, seemingly simple rook endgame. If it was black to move, he would have a very easy draw. See for example this variation…

But it is white to move. That makes all the difference in the world. But how? That’s maybe not so easy to spot. Do you see how white can win? Solution…

Here is another one!

Some moments after I finished this post, I surfed to chess.com. Chess.com shows every day a new puzzle. Sometimes these puzzles are quite hard to solve. This one is also a bit tricky. See the second diagram.

It is white to play and win. The first move is obvious. But then it gets a bit tricky. Do you see how to solve this one? Solution… 

Goes without saying that not all rook endings end in a draw!