Have you ever missed a train, and then had to wait an eternity for another to arrive?
That analogy can be compared to Manchester United's never-ending hunt for a central midfielder, with the last major additions in the position being Anderson and Owen Hargreaves in 2007.
Two years ago however, United were linked with an up and coming 20-year-old midfielder, only to miss out on his signature - and are now watching him blossom into one of Europe's most talented players.
He is now at Borussia Dortmund, playing a starring if unsung role in their passage to the Champions League Final, and is valued in the region of £20 million. If United wanted to sign him, the chances are they would face a real fight from Dortmund and may have to pay closer to £30 million to prise him away.
It wasn't always like that. Back in 2011, just two summers ago, Gundogan was certainly on United's radar, when he was playing for FC Nuremburg.
"Manchester United would obviously be a dream club."
The price tag quoted for his signature back then was a relatively insignificant 10 million Euros, a real bargain, but despite Sir Alex Ferguson's reported interest in the player, it was never followed through.
That summer, in 2011, Gundogan was bought by Dortmund for a bargain price of £4.8 million.
And if you think that was cheap, consider the £100,000 Nuremburg paid Bochum to sign him as a teenager back in 2009.
So to the future? It was claimed by a Spanish website two days ago that Gundogan is still a target for Manchester United, with him high on the club's shopping list.
However the chances of the club making good on their intentions to sign the 22-year-old have taken a knock by the player himself, who says he wants to continue at Dortmund, and also explained why he previously described United as his dream.
He said: There is nothing wrong with it, to answer the question with yes. Everyone had a dream that he wants to experience once a day as a child. It was always my dream to play in England or Spain once.
"I can imagine a contract extension very well. Wholly I know I'm going to play next season at Borussia Dortmund."
Did United miss out on Gundogan? Have they missed out for good?
image: © peterfuchs