There is nothing more exciting in the world of football than when a new talent, fresh-faced and full of life, laces up his boots for the first time and starts to dazzle fans. What happens after those spectacular first moments, however, is anyone's guess.
Some players will go on to fulfill those sky-high expectations imposed on them from the first days of their career, becoming legends thanks to a combination of hard work and good luck.
Many others though will never quite make the grade expected of them. It may be due to a failing on their part, or some extenuating circumstance that made it impossible to reach their potential; but when this happens, we can only look back and wonder, what if?
We have trawled through the archives of football history to bring you 10 of the top young stars who, for one reason or another, could not live up to expectations.
The man they call "El Burrito" (little donkey) was included in Argentina's 1994 World Cup squad for the United States alongside one Diego Armando Maradona, and it was fully expected that the supremely-talented No. 10 would assume the playmaking role for the Seleccion once his idol hung up his boots.
Despite a string of high-profile European moves and appearing in three World Cup finals, Ortega could never quite match up to those astronomical expectations. There were moments of brilliance, but they were all too often overshadowed by indiscipline on and off the field, which meant he never stayed too long in one place.
The last few years of the Burrito's career saw him return without success to River, where he played out a highly public battle with alcoholism and was turfed out for a mediocre end in Argentina's lower divisions. A less-than-fitting end for the man dubbed the natural heir to the great Diego.
Ask most Boca Juniors supporters, and they would be loath to agree that Juan Roman Riquelme has failed to fulfill his startling talent. The Xeneize faithful can point to three Copa Libertadores winners' medals, one Intercontinental Cup victory and five national championships for starters, all picked up with the brilliant playmaker at the heart of the team.
Outside of the Bombonera, though, the world has rarely seen the best of Roman. His time at Barcelona was a failure, exacerbated by the tactics of Louis Van Gaal, who insisted on playing him out of position on the wing, and Riquelme's awful personal relationship with the Dutch coach.
The Argentine found more success a step down at Villarreal, where he played more than 100 matches and led them to their best-ever league finish, but still the success his talent merited would elude him in Europe. This success eluded him in the national team as well, where over 11 years' playing time did not yield a single senior trophy.
This Montevideo native was one of the most graceful, supremely talented men ever to step onto a football pitch. Unfortunately, as "El Chino" would most likely admit himself in one of his more candid moments, he was also by far one of the laziest.
The fact that he loathed training and the physical part of the game, as he freely confirmed to Montevideo.com (Spanish), did not hold Recoba back too much. The Uruguayan spent 11 years with Inter during the 1990s and 2000s, racking up over 300 appearances in Italy, almost 100 goals and more than enough material to fill many a YouTube highlight reel.
His laissez-faire approach to the game, however, always made him at best an inconsistent performer. Catch Recoba when things were going his way, and he could win you a game single-handedly. On a bad day, you would barely realise he was on the field.
At 36, El Chino is still starring, back in his native Uruguay with local giants Nacional. But he will remain one of those players who could have conquered the world with a little more drive and application.
To look at pictures of the young Adriano, as he is above, at just 20 years old and with all the talent in the world, is almost an embittering experience. The wandering striker serves as the perfect example of how it can all go wrong for football's hottest prospects.
The Brazilian moved to Inter for a hefty fee of almost €10 million and showed enough during a lengthy apprenticeship with Fiorentina and Parma to convince the Milan club he was ready for the big time. But amid myriad stories of nightclubs, parties and a lack of commitment, his time at the San Siro was nothing but a big disappointment.
He has been out of the game since 2012, a sad end for someone barely into his 30s.
While his name now may be only of interest to those who spend their days leafing through dusty football archives, life was a lot different back in 1998 for this outrageously skilled youngster. He wore the No. 10 shirt throughout Brazil's trip to the World Cup final in France and would later become the world's most expensive player with a move to Real Betis.
Seven years in Spain, however, did not pan out as expected, and the attacking midfielder finished his time with Betis as a fringe player. Later moves to Flamengo and Bordeaux failed to galvanise his career, and he soon became one of football's great wanderers.
Denilson's time in football finished with stints in the UAE, China, the United States and Greece, but by this time he was a pale shadow of the kid who looked ready to take on the world. At the age of just 32 he had retired, with over 60 Brazil caps to his name but with none of that early potential fulfilled.
When his career started in a blaze of glory during the last few years of the 20th century, the English press were convinced they had found their next natural goalscorer, a worthy heir to the likes of Geoff Hurst and Co. The fact he is here on this list should tell you how that panned out.
The Liverpool youngster looked unstoppable during his teenage years, as he burst onto the scene with two goals in the 1998 World Cup against Argentina that were of unforgettable quality. International tournaments were always Owen's forte: He went on to net in Euro 2000 and 2004, as well as the 2002 World Cup.
The fates conspired against the diminutive goalscorer, however, with injury robbing him of some of his best years. Add to that an at-best average spell with Real Madrid in which he never found the form that had seen him become a star at Liverpool, and it is fair to say that from 2004 onward we never again saw the best of Michael Owen.
Owen finished his playing career this season with Stoke City, and at the age of 33 the striker has now hung up his boots.
In his later years, George Best was fond of recalling the possibly apocryphal account of how a hotel waiter, upon seeing him in his room surrounded by thousands of pounds in cash and with a Miss World contestant on top of him, asked as he handed over two bottles of champagne "George, where did it all go wrong?"
Including the Northern Irish legend in this list feels almost like repeating the befuddled waiter's questioning. Best gave so much to the beautiful game and received fame and riches in return, but it could have been so much more.
At just 23 years old, the bewitching winger was at the pinnacle of his profession, having lifted the 1968 European Cup with Manchester United (the first English team to win such an honour) and himself being named the European Footballer of the Year. From there, however, and despite a handful more decent seasons, there would be no more trophies, and the slide had begun.
Best finished his career moving from club to club, including a notable spell in the NASL of the United States. He left his mark on British and world football, but perhaps we will never know why it went wrong for the nascent star after reaching the top so young.
Part of the same Ajax youth system that brought up the likes of Ruud Gullit, Frank Rijkaard, Marco van Basten and many other stars, Kluivert was supposed to be the next great name to represent the Netherlands on a world stage.
Quick on the ground, strong in the air and blessed with dazzling control, the graceful yet physical striker was a Champions League winner at just 18 years old, and great things were expected. His first move though, to Milan, turned out to be a dud, and despite some impressive numbers for Barcelona as part of the Dutch legion recruited by Louis Van Gaal, he could fire neither the Blaugrana nor his country to sustained success.
After leaving Barca, Kluivert endured mediocre, always short-term links with a number of second-grade clubs across Europe. Newcastle, Valencia, PSV and Lille all saw the forward pull on their shirt, but to little glory, and it was in obscurity that he hung up his boots in 2008.
It may still be too early to call disappointment on the career of Freddy Adu, particularly since the Bahia forward is still shy of his 24th birthday. Considering the hype that surrounded Adu's first steps in professional football, though, it does seem unlikely that he will ever be the player we once believed.
The perfect definition of a child prodigy, the Ghana-born whiz kid came to prominence in the U.S. media at the age of just 13, and at 14 was making his MLS debut with DC United. 2007 saw a European move come onto the horizon, with Portuguese giants Benfica representing the next step to conquering the football world.
But his time in Lisbon was nothing short of a disaster. Adu spent four years with Benfica, the vast majority of which he was farmed out on loan, and when it became clear he would not make the breakthrough, a humbling return to MLS with Philadelphia Union beckoned.
For 2013 the youngster has taken the daring step of moving to Brazil with Bahia, where he will continue the task of rebuilding his career.
The case of Duncan Edwards is by far the saddest in our list. Tipped to be one of the greatest players ever to represent England, his career was cut short in the most tragic of circumstances.
A wing-half, or defensive midfielder to use current football parlance, the Manchester United star was judged to be a future England captain, and at 21 he had already picked up 18 caps in a time when the international calendar was far less packed, scoring an impressive five goals.
A measure of the esteem in which he was held can be gauged from Terry Venables, who stated that if he had survived the Munich air disaster, it would have been him and not Bobby Moore who lifted the World Cup as captain in 1966.
Tragically, Edwards did perish due to that icy evening in 1958. The plane carrying United back from a European Cup match against Red Star Belgrade crashed during take-off, killing him and seven other members of the famous "Busby Babes." Football mourned the loss of one of its great promises, and even today it is wondered what Edwards could have achieved in the game.