Guardiola hasn't been sacked, but it is not only because he knows his worth, it is also because he is the best coach in the world in terms of influencing players and making them better. I doubt that Klopp would ever be sacked as he is very similar and both have their successes. They would rather leave a club in agreement with the clubs' bosses, but not get just fired I suppose. They are also different from Mourinho who likes to provoke everyone, including officials from his own clubs. He is more likely to get fired at the end of his engagements than to go just because he doesn't want to stay anymore.
Klopp may have not gotten fired this season, but if he keeps getting bad results another year, I am not sure how long they can survive.I do not know how much money they spent so far on his tenure, but it is not very little, and I feel like he had some great achievements they couldn't otherwise, and that is why he deserves to be getting some good results one way or another, but if he fails to get it and he keeps the team at bad place for a long time, and not get back into the top four, which is harder nowadays, then he is not going to be cherished forever. He may end up getting "fired", of course he can come to an agreement and leave himself to save face, but at the end we would all know that he would be fired.
Yes I think some people thought that this could be the end for Klopp this season already, but then I thought that he achieved so much and is the reason for so much joy within the team, the whole club and the fans that it would be the wrong move to sack him after one bad season even if it is Liverpool that we are talking about here. You'll never walk alone and so on you know?
He was the one to bring them titles and then it doesn't go very well and they sack him, that wouldn't fit very well into their philosophy and their main slogan.