For a team like Chelsea and considering their situation, the first thing is more important and I think Pochettino should do many hard words at players' mentality because of the bad season they had.
That's the only way to push chelsea not to repeat the same mistake again like the previous season. Pochettino being chosen as a new coach for chelsea and it has become his responsibility to build the club even better by developing the mentality from the players.
As you can see that some players like mudryk have poor performance. Not even a single goal being made by mudrk last season. That proves that if this guy doesn't have good mentality to play in EPL.
I would say he was good enough, but it's not enough when it comes to the EPL caused by it needs a very strong mentality. The most competitive competition in europe.
It's not the same as when he was playing in shakhtar. Mudryk shall have to remember if he playes in EPL now. The competition was far harder compared in the previous league with shakhtar.