Works just fine for Real Madrid.
I would argue that United's issue is not throwing money as such but throwing money at non-top players. Apart from Pogba (who flopped, but still) and Casemiro (who has done well, but is sadly a second-hand signing), there are no signings made by United over the last 10 years who were considered world class at the time of joining(and for anyone saying United create stars, not buy them, this is not the 90s or mid 2000s anymore. No class of 92 coming through and no Vidic or Evra available on a cheap). One could say Sanchez, but he was already on a decline when signing, which later turned out to have been a permanent thing. Similar to the Torres at Chelsea situation.