There's nothing worse than seeing a talented player's career fizzle out.
Whether that's down to injury, their own mentality, or sheer bad luck, we've seen it happen all too often.
As exciting as it can be to watch youngsters rising to prominence, even the likes of Erling Haaland should be treated with caution.
It's simply impossible to predict how any footballer's career trajectory will pan out long-term.
The Reds supporter put forward the two signings of Anthony Le Tallec and Florent Sinama Pongolle in 2001 as particularly disappointing, as the duo arrived to huge fanfare and just couldn't deliver.
The names did not stop there and hundreds of fans have been weighing in with the most frustrating cases in recent memory.
We've picked out a few of the best.
The Brazilian at his peak was described as the heir to his compatriot Ronaldo. Then, the death of his father in 2004 saw him turn to alcohol and his life spiralled out of control. A very sad story.
While it was always going to be difficult for the German to maintain that high of scoring the winning goal in a World Cup final, Götze has been awfully unlucky with injuries and failed to make the grade at Bayern Munich. After returning to Borussia Dortmund, he was diagnosed with a metabolic illness.
That night against Barcelona has never been forgotten, but it wasn't a total one-off. Wilshere looked like the next great English midfielder. Unfortunately, he made just 125 appearances in a decade at Arsenal and hasn't impressed at either Bournemouth or West Ham since.
Many feel Balotelli only has himself to blame, his unconventional behaviour proving entertaining but not conducive to staying at the very top. The Italian won the Champions League and two domestic titles at his peak but he's now with Brescia.
Johnson has spoken candidly about the off-field problems that plagued his short career after becoming a prospect at Manchester City. Scoring his first goal at 19, the midfielder drew comparisons with Michael Ballack. He was released in 2012 aged just 24.
Pato really did look special at AC Milan. By the time he was at Chelsea, he was a shell of that player and ended up spending two years in China before returning to his native Brazil.
The playmaker was once described - by David Ginola no less - as the most gifted Frenchman of his generation. Sadly, the politics of the 2010 World Cup seemed too much for him amid rumours Nicolas Anelka and Franck Ribery had deliberately frozen him out of the team by not passing to him. Gourcuff is now a free agent.
Rossi only ever scored one league goal for Manchester United. He had stood out in the domestic cups and was tipped to break into the first team at Old Trafford. Injuries had their way and although he's had a decent enough career in Spain and Italy, he's never reached the heights expected of him.
In spite of those incredibly long legs, Diaby played with grace and could dribble past anyone. Arsenal thought they had the ultimate box-to-box midfielder on their hands, but it was just one injury after another.
It's easy to laugh now at Sir Alex Ferguson's comment that Jones was capable of becoming United's best player of all time. During his time at Blackburn, however, he barely put a foot wrong and it was only his injury record that sparked his decline.
"He used to play for Barca, but Stoke is just the same," so the song went. Unfortunately, it is not the same at all and there's a reason Bojan played for seven clubs in eight seasons. Fame was a struggle for a man once seen as the future of Barcelona and his career was placed under unfair scrutiny by the media.
Questions immediately started to be asked about the tricky midfielder's attitude at Tottenham. There certainly wasn't a mark against his confidence. A longer spell with QPR followed and he's now with Benfica, still playing with panache yet not quite making it to the very top of the game.
Can you believe Anderson is still only 31? Winner of the 2008 Golden Boy award, he later kept finding himself in the headlines for the wrong reasons, falling out of bars in the early hours and crashing his car on a night out when he was supposed to be recovering from a knee injury. The Brazilian also never took kindly to having to play a more defensive role after Cristiano Ronaldo's departure prompted a shift in United's tactics.
Ferguson rated him more highly than Paul Pogba. Morrison was a part of the United side that won the FA Youth Cup. Yet as a youngster he couldn't help but keep getting in trouble and the 27-year-old has played for 10 different clubs in eight years. At six of those, he's failed to get into double figures for appearances.
It's no coincidence there are so many United players mentioned. Playing for the Red Devils at any level brings with it a huge weight of expectation and it just didn't seem like Januzaj wanted it enough. The winger is now at Real Sociedad after a pretty underwhelming spell at Sunderland.
Eduardo Da Silva
The forward was never the same after that horrific leg break. It came just as he was finding his feet in the Premier League, too. He was sold to Shakhtar Donetsk for just £6m.
Many forget that Richards was part of that first Manchester City side to win the Premier League in 2012. Two years later, he was sent to Fiorentina on loan and made just 10 appearances. It got even worse at Aston Villa, mind you, and he ended up going over 500 days without featuring despite being fully fit.
Walcott's career has hardly been a waste like some of the aforementioned names. Even so, it's hard not to feel he never lived up to the potential that made Sven-Göran Eriksson take him to a World Cup without even watching him. That's how hyped up he was as a teenager at Southampton and nowadays, nobody can really remember why.
Hatem Ben Arfa
The former Newcastle star joined Real Valladolid on a short-term deal in January. Before that, he'd been without a club for six months and that's nothing new to him - in 2018, he went a whole year without playing! There have always been doubts about his mentality which have arguably led to him squandering his talent.
It's easier to come to terms with when players have wasted their potential through their own carelessness.
Amidst those cautionary tales, there have been some genuinely sad stories where cruel fate has intervened and robbed these prodigies of a potentially world-class career.
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