The case of PSG with lot of quality players with nothing to show for it at the champions league is the same as what happened to Chelsea this previous season. Too many talented players but couldn’t put them into good use becomes a wasted effort and resources by the club.
Chelsea don't have many talented players, but they have many overrated players and they make it worse by spent higher than the players' market value.
The problem of PSG they only have few talented players and their opponents are weak, so when they always win in Ligue 1, there's no club can become their rival to learn and improve their club. Lack of motivation and overconfident are the big enemies for club which is already in top position, Arsenal is one of them.
Chelsea few months back was one of the best club in Europe and England with their performance and quality, but suddenly change of ownership create problems, and now they are in the worst position and this all is not comparable with the PSG because these both clubs are completely different and have conditions and other environment are also not same which is surely problem for them but failure of PSG in Europe is surely problem because just having too many stars are never been guaranteed of success here you need better body language of players and playing chemistry as well which is not in PSG because players are not comfortable on their positions, and they are also having not domestic competition even this is not solid but still a reason here they need to work on hopefully things will be changed.