What you say is a little bit true in my opinion, when a coach fails to meet the expectations expected by a big team like Madrid then it is certain that the coach's career will end at a club like Real Madrid, because after all Real Madrid have high expectations every season on their coach and even they are willing to spend a lot of money to be able to meet all expectations to be able to win trophies in all competitions they have participated in so far, So it is very natural that Madrid management will fire their coach even halfway when he sees his team actually down.
But I think for now it's different what happened with Barcelona, if in the past when Barcelona was coached by Quique Setien and Quique Setien failed to get a trophy for Barcelona of course it is not strange and very natural if he was fired for his failure to coach, because Barcelona at that time which had indeed spent a lot of money, but when Barcelona was only able to win second or third place this season and if they also failed to win the champions League trophy of course I think Xavi will still be very successful at Barcelona this season, because after all Xavi has managed to make a lot of changes at barcelona with only modest player capital and also the financial condition of the club which currently has a lot of problems, so honestly I don't want to say if Xavi is 100% a failure in barcelona.