Barcelona have many quality players, but some of them are often injured.
Xavi had to find a way to keep Barcelona's players fit. Moreover, the availability of players becomes very important in the midst of an increasingly crowded schedule. The problem of defense should be the main focus to be improved, although it has brought in a number of players in this sector, but they do not look cohesive at all.
What you say is true, but over time Xavi will surely be able to overcome any shortcomings that still exist in the Barcelona team, because in general Barcelona have been very strong this season and Barcelona should only focus on beating the team that is stronger than them, namely Real Madrid. which until now is still very consistent in all matches.
It was proven through ten matches played by Real Madrid, only one match ended in a draw, the rest was only a win. This indicates that Real Madrid is Barcelona's toughest opponent this season.