-Snip-
He believed he had all the required resources already, but everything happening this season was just as a result of last years effort channeled inot getting the trophies, they played so many games/too much games and that was reflecting in the players somehow this season, signing new players could have helped resting some of this players but it's done already and there are no room for excuse, just as Mancity had no room for excuse, to me their situation is alike just that Realmadrid did performed better than them and still hanging tight to UCL and Copa even though this season could end with them having no trophies

Even currently Carlos Ancelotti is one of the best in business but still he fails to keep things on level which is hurting them badly this is going to be huge setback as now chances are limited for them to challenge Barcelona at the top for title race.
To be honest while get the reason he might not want to sign more players since when these injured players arrive there will be limited game time and this often affects the team in general in the long run. I think this was somehow the issue Tuchel suffered from at Chelsea where there where so many players to pick from and that's would sometimes cause issues and some might end up leaving which somehow affect the team performance.
Anyway, Real Madrid are currently facing injury crisis like Barcelona last season after stressing set of players continually for years. In the current state Ancelotti needs to sit up straight and do the needful get more players for rotation because I think this same injury crisis is inevitable next season except there's some sense of rotation.