What actually makes a football team great?

When you look at winning teams, there are so many different pieces involved. Is it just having amazing players, or is it something bigger behind the scenes?

On the field: Star strikers, a strong midfield, solid defense, and a reliable goalie.

Behind the scenes: A great manager, smart tactics, good owners, plenty of money, and top-class training facilities.

For experienced fans, what do you think is the single most important piece? Can a team win big trophies just on player talent alone, or does everything start with a great manager and board?