You wrote an original comment in defence of the posters who were suggesting it was inevitable that Garnacho will move to Real Madrid.
Of course I can't give you examples, because I have zero knowledge of the inner workings of the Real Madrid administration, now or at any time in the past.
But unless we are to assume that all of Madrid's transfer desires are inevitably realised, then we need to assume that they have coveted other players than those they've signed. And it is patently obvious that Manchester United has had numerous players throughout their history who were superior than their Real Madrid counterparts at particular moments in time, and indeed who were among the best players in the world. Unless you then also assume that these great players simply weren't of interest to Madrid (when obviously players like Best, Law, Charlton, Robson, Scholes, Keane, Schmeichel, Ferdinand, Stam, etc., etc. would have been of interest to every major club at their peaks, which were all spent with us), then you're forced to conclude that it is possible for Manchester United to hold onto many great players regardless of the interest of other football clubs.