Maybe it is simply an identification of somebody who has that special ingredient to become a 'United player', a term that is difficult to define but one that every supporter will fully understand.
I remember watching Wayne Rooney in the 2002 FA Youth Cup final for Everton against Aston Villa and being blown away by his talents. I tracked his progress and always hoped he would join the Reds and was delighted when it came sooner than expected after his exploits at Euro 2004 for England.
Roy Keane was another such example of a player United simply had to sign. His box-to-box work at Nottingham Forest made it clear he was probably the only midfielder around who could replace Bryan Robson. Following Forest's relegation, the opportunity to land the Irishman presented itself and I was saddened when Blackburn Rovers appeared to have won the chase for his signature. Thankfully, Sir Alex was able to pull off a British record swoop in the nick of time.
One magical moment from Dimitar Berbatov, pirouetting like a ballet dancer at Charlton Athletic before scoring in style, made me realise the Tottenham striker was something special. I had a conversation with a cab driver the following day and stressed it was 'world class'. While not agreeing with his assessment that the Bulgarian was Spurs' best-ever striker, I felt he certainly had the skills worthy of gracing Old Trafford.
Some slipped through the net, perhaps going back for me as far as Paul Gascoigne. I would specifically watch Brazil's international matches, where possible, to initially see Juninho and then Ronaldinho in action. United reportedly showed strong interest in both South Americans. Again, I feel they had the flair required to make an impression in Manchester and was disappointed they never wore the red shirt.