For many of the world's elite clubs, the way their squad is built can ultimately define success on the pitch for generations to come.
If major errors are made in the recruiting process, it can take a long time to change philosophy, player perception and more importantly, progression.
For this piece, we're going to analyse the current policies of four of the best clubs in world football: Manchester United, Barcelona, Manchester City and Real Madrid.
All four are considered extremely successful, but the way they have built their current squads are very different indeed.
There are two distinct trends that appear when looking at each club.
United and Barcelona both have a spine of experience that have been with the club for at least eight seasons or more.
Rio Ferdinand, Ryan Giggs and Wayne Rooney have played 43 seasons between them. Carles Puyol, Andres Iniesta and Lionel Messi have 34.
That is certainly not the case when looking at Manchester City and Real Madrid.
Vincent Kompany, David Silva and Sergio Aguero currently have just 10 seasons between them while Sergio Ramos, Xabi Alonso and Cristiano Ronaldo total 16.
Of course, experience does not guarantee wins or trophies but it does bring stability and continuity to a club, which in turn promotes respect and spirit.
For new additions such as Robin van Persie and Jordi Alba, the attractions of coming into a settled dressing room with tradition is sometimes a determining factor.
Manchester City lost out on van Persie this summer, leaving Roberto Mancini to claim it was the main reason for United potentially regaining the EPL title this season.
Everything so far points to Barcelona and United's blend of experience and new additions combining to give their club the very best chance to succeed.
However that's not altogether true, as Real Madrid and Manchester City fans will tell you—club loyalty doesn't always make a difference.
And they would have an excellent point, with both teams currently holding their respective league titles.
The turnover of players is far greater at both clubs with huge money deals, both in and out, continually exciting fans and media as well as raising expectations.
Madrid still have the ability to pay for anyone they want although the "galactico" days are probably over, while Manchester City's Abu Dhabi 2008 takeover has given the club unprecedented strength in the transfer market.
The old argument "you can't buy a title" may have been put to bed by City winning the EPL after a dramatic 3-2 win over QPR on the final day of last season.
Madrid's La Liga title wasn't quite so close but just as impressive, finishing nine points clear of Barcelona.
The turnover of players is significantly more at these clubs, yet the success is there for all to see. Many chairmen spend money for results and that's exactly what both clubs have provided.
In conclusion, it's evident to see that both methods work at an elite level.
Each bring results, although it seems Real Madrid and Manchester City's success will be intermittent until their squads become better settled at the club.
United and Barcelona's models seems more desirable and are set up to have success in the long term.
Of course, that will not guarantee results, but it's certainly giving the manager the best chance to achieve their goals.
Moving forward, it's evident that the player turnover will remain for some time at Madrid and City, including their own managers.
Both Jose Mourinho and Mancini have been heavily linked with moves away from their respective clubs. If they leave, it can create a knock-on effect. Players like stability and want to play under the same manager.
Although Tito Vilanova is in his rookie season, many expect him to be at the helm for years to come barring further health problems. With the backing of players, the atmosphere and team spirit that is created is invaluable.
The proven model of this is Sir Alex Ferguson at Manchester United. Twenty-seven years and counting, his respect amongst the players has helped him build one of the most harmonious squads in world football.
It is no coincidence that both United and Barcelona have sewn up their respective league titles with plenty of games to spare this season.
Madrid and Manchester City are not going away and will continue to win trophies in the near future, but it's their main rivals who will continue to be more consistent thanks to the current squad they have created.
A manager's goal isn't to ensure that every team member is great; it's to ensure that collectively they'll be great—there's a big difference.