Loan spells are mainly devised to nurture development in talented young footballers.
Premier League clubs so often send promising players to lower league clubs, or abroad, in a bid to get them experiencing regular game time at senior level.
More often than not, those players return to their parent clubs more accomplished footballers having been exposed to life in the first team, and the coaching staff that sent them out in the first place generally reap the rewards.
Watching Arsenal defeat Olympiacos in the Champions League on Wednesday night, I was impressed by the performance of Costa Rican attacker Joel Campbell.
The 23-year-old arrived in North London back in 2011 and was indeed not ready for first team football with the Gunners.
Arsene Wenger opted to send Campbell to French club Lorient and he has since spent time in Spain with Real Betis, in Greece coincidentally with Olympiacos and back in Spain with Villarreal.
It was evident that his time away from the Emirates Stadium has him well-equipped to be an Arsenal regular, swiftly prompting the idea for this Top 5 you are reading.
Tribalfootball.com has decided to take a look at some loanees before Campbell who returned to their parent clubs much better players than when they left and have impacted things for the good at their original home.
TOP 5 RETURNED LOAN STARS
5. Aaron Ramsey (Arsenal)
Loan spells with Nottingham Forest and Cardiff City
The Welsh midfielder first arrived at Arsenal from Cardiff in 2008 as a skinny 17-year-old who promptly made his Gunners debut in August of that year.
In what is a more curious loan case than we are used to, Ramsey was sent to Nottingham Forest in November 2010 despite chalking up close to 50 appearances for Wenger.
A horror tackle by Stoke City defender Ryan Shawcross badly broke the leg of Ramsey in February of that year and the move to Forest 10 months later was seen as an astute way of getting much-needed match fitness into the legs of the Caerphilly product.
Ramsey made five appearances for Forest boss Billy Davies before returning to North London in January 2011.
A second spell at Cardiff soon followed as the Gunners sought further conditioning for their promising attacking midfielder with 'Rambo' playing six times for his former club the Bluebirds.
Since returning to Arsenal for good late in the 2010/11 season, Ramsey has become one of Wenger's key players in central midfield as an attacking outlet.
His best campaign came in 2013/14 when he scored 16 goals in 34 appearances and to this day, he continues to be one of Arsenal's prime movers, as demonstrated by his past two performances against Sunderland and Olympiacos after returning from a hamstring injury.
4. Ross Barkley (Everton)
Loan spells with Sheffield Wednesday and Leeds United
The Toffees midfielder is fast-becoming one of England's best players in his position.
Another to return from a bad leg break, Barkley burst onto the scene in 2010 before making six Premier League appearances in 2011/12.
His first loan stint commenced in September 2012 when he was sent to Sheffield Wednesday.
During his time at Hillsborough, Barkley appeared in 13 Championship games up until mid-November, scoring on four occasions. He returned to Goodison Park but was soon farmed out to Leeds United where he appeared four times for the Whites.
Barkley was back at Everton for five top flight matches to round out the 2012/13 campaign. Since then, the 22-year-old has established himself as a Toffees regular with 93 appearances in all competitions which has yielded 16 goals and 12 assists including six goals and five assists in 15 Prem outings this term.
After some up and down form, Barkley is now fulfilling his enormous potential as one of England's best attacking midfielders as evidenced by his regular involvement in Roy Hodgson's Three Lions setup and his influence in Roberto Martinez's ever-improving Toffees outfit.
3. Thibaut Courtois (Chelsea)
Loan spells with Atletico Madrid
The Belgian goalkeeper joined Chelsea from Genk as a 19-year-old in 2011, arriving in West London with enormous wraps.
Courtois signed a five-year deal with the Blues at a time when Petr Cech was the undisputed number one, suggesting that he was certainly one for the future.
Just weeks after landing at Stamford Bridge, Courtois was sent to Spanish outfit Atletico Madrid and quickly stepped into the boots which had previously been filled by David De Gea, who had been signed by Manchester United.
In Courtois' first season with Atleti, the Rojiblancos took out the Europa League with the now 23-year-old keeping a clean sheet in the 3-0 victory over Athletic Bilbao.
That campaign, he made 52 appearances in all competitions before being loaned back to Atletico for the 2012/13 season.
His second spell kicked off with the UEFA Super Cup triumph over parent club Chelsea in a season where the Madrid outfit also took out the Copa del Rey. Courtois played 46 times for Diego Simeone that term.
Still the Blues weren't ready to throw him into the Premier League fray and the 32-time capped Belgium international returned to the Vicente Calderon Stadium for the 2013/14 campaign. This proved to be another successful move for Courtois as he was an integral part of the Atleti side which won the La Liga title - the club's first since 1996.
Courtois was also involved in the Champions League final but he and his Atletico teammates were down by local rivals Real Madrid 4-1.
Now was the time for the Bree native to take the gloves in London and he made quite an impact in his 32 league outings as Jose Mourinho lead the Blues to the 2014/15 Premier League title and the Capital One Cup.
Courtois has undoubtedly emerged as one of the top goalkeepers in Europe and in the elite few in England over the past 18 months.
It's frightening to think just how much success he will considering he has already won eight trophies at senior level for three clubs at the ripe old age of 23.
2. Harry Kane (Tottenham Hotspur)
Loan spells with Leyton Orient, Millwall, Norwich City and Leicester City
Kane is one major success story from the loan system.
The 22-year-old striker came through the Tottenham Hotspur youth academy having spent a season with North London rivals Arsenal as an eight-year-old.
At 17, Kane move to Leyton Orient for the second half of the 2010/11 season. He scored five goals in 18 outings in what was a successful spell in League One.
His Tottenham debut followed in August 2011 in a Europa League qualifier against Heart of Midlothian before he went on to feature five more times in Europe's second tier competition.
Kane then shifted to the south of the capital to join Millwall in January 2012. During his time at The Den, the Chingford-born attacker struck seven times in 22 Championship outings for the Lions, finishing with nine goals in 27 appearances for the club.
Still not ready for regular first team action with Spurs, Kane then headed up to Norfolk to join Norwich City in the summer of 2012. A broken bone in his foot ensued, and then he was recalled in February 2013, after making just five appearances for the Canaries.
Less than three weeks later, Kane was off to Leicester City where he hit the back of the net on two occasions in 15 outings, including the Championship play-offs.
Tottenham are now ready to show more faith in the England youth star and he featured 19 times for four goals in 2013/14 before his breakthrough campaign at Premier League occurred the following campaign.
Kane was irresistible for Mauricio Pochettino last season, firing home 31 goals in 51 appearances in all competitions, including 21 in the Premier League, landing him the PFA Young Plater of the Year award.
The 'Harrykane' is now considered one of the English top flight's premium attackers with his 10 goals in 21 outings (eight in 15 in the league) proving he is not a one-season wonder.
1. Joe Hart (Manchester City)
Loan spells with Leyton Orient, Blackpool and Birmingham City
England's top goalkeeper has not always been at the forefront of the game at top flight level.
Hart joined Manchester City from Shrewsbury Town in 2006 but at 19 was not thought of as ready to pitch up in between the sticks at Premier League grade.
In January 2007, the Shrewsbury-born shot-stopper made his way to Merseyside where he linked up with Tranmere Rovers for six League One appearances.
April the same year saw a move to Blackpool take place and a further handful of third tier matches added to the experience of the talented custodian.
Hart's England debut in June 2008, having notched up 26 Premier League appearances for City under Sven-Goran Eriksson, indicated he was set for a very lofty career.
However, Shay Given's arrival at City in January 2009 forced the now 27-year-old to head to Birmingham City in the summer of that year. He went on to feature 36 times in the top flight for the Blues in what was an extremely imposing stint at St Andrew's.
That campaign in particular definitely proved that Hart was ready to be City's undeniable number one and since that day, he has not looked back, missing just nine league games in five years prior to the beginning of the 2015/16 season.
During that time, Hart has won two Premier League titles, one FA Cup, one Capital One Cup and a plethora of England caps to be the top man in his position and take out our number one of loan stars who have returned to their parent clubs as better players.
