The overriding priority is something called balance!
There is no point in bringing in players If that balance doesn't work, potential, does not mean adapting to the teams make up, partnerships within shape, is necessary for the team to gel.
The number of times someone has mentioned the front players don't work well together is what is argued over, discussed. If a player regardless of talent, doesn't fit into that balance, it is difficult for the rest of the team to adjust to.. The dynamics of shape, formation and tactics. The need to adapt to changes and other issues which includes injuries,
Team building is what is done in training, assessment, tactics, positional awareness, variables and opposition.
Preparation is key, communication, planning, strategy, balance!
Set pieces, free kicks, for and against, corners, marking, zonal, defensive shape, attacking shape.
Work rate, fitness, mental strength, bravery, keen to learn, commitment, and an understanding of the structure of the club and its aims. To buy into the ethics of what the manager and coaches are trying to achieve.
The balance of the team and a winning attitude is why we have a manager and coaches. Spending time and money on the best aspects of football at this level is important. But if it's not working, it needs changing and we do have a manager that understands this.
One player can make a difference, but you need eleven players to make a team. And you need balance to compliment the different abilities of individuals and partnerships, required in a good team.