It is very easy to look at successfully built teams and just focus on the investment they made in the players that are actually at the team. Because these are the players that are actually making a difference, your attention is naturally drawn to them, and to the processes that led them to being there.
But some of the most successful teams, in any sport, not only acquire talent, but they trade talent too. It is the selling, and not just the buying, that is essential to smartly assembled teams.
Liverpool sold Luis Suarez, Philippe Coutinho and a plethora of young players to build their Jurgen Klopp juggernaut.