Disclaimer: English isn't my first language so there may be some mistakes.
Serie A 2020/2021 is three games away from its conclusion and Juventus is in fifth place. How could the team which won the last 9 italian championships in a row and which counts among its ranks world-class champions such as CR7, Dybala and Chiellini sink so low? Here are 4 reasons why:
AN UNEXPERIENCED MANAGER
Andrea Pirlo, the Maestro, was one of the most elegant deep-lying playmakers in the history of football but probably he will also be remembered as the worst manager in the history of Juventus. The main reason is that Juventus is the first team he has ever trained. More: he has never been either an assistant coach (Zidane) or a reserve team coach (Guardiola). Zero experience.
A lot of Juve fans complain about poor quality in the midfield. I don't agree on this. The real problem is lack of personality. Juventus midfielders are either new in the team (Arthur, McKennie) or too young (Bentancur) or just not charismatic as a character trait (Rabiot, Ramsey). This personality problem can be partially solved by playing in a three-man midfield because in this way players can share responsabilities. However Juve kept playing with a two-man midfield. A recipe for disaster.
Previously I mentioned CR7, Dybala and Chiellini as the Juventus world-class players. The last two were injured most of the time. Many other players had various injuries. As a result Juventus almost never had the whole squad available. Injuries are a matter of luck but they're also a mistake if you build a squad with many player which have a higher risk of injury. Yes, I'm talking about you Ramsey (not only him though).
A BAD CHOICE FROM A WISE MAN
Andrea Agnelli, Juventus President, was the person who made possible Juve renaissance after Calciopoli scandal by making good choices. He appointed Giuseppe Marotta as CEO. He hired Antonio Conte as manager. They aren't the only good choices he made (another awesome choice was to hire Massimiliano Allegri after Conte's departure) but it's emblematic how Inter won the Serie A this year with both Marotta and Conte amongst their ranks. How the turntables, right?
This season Agnelli made the choice which condemned Juventus to death: he sacked Maurizio Sarri and he hired Pirlo. Sarri's Juve had "bad" midfielders, Pirlo's Juve have "bad" midfielders; Sarri's Juve had a lot of injuries, Pirlo's Juve have a lot of injuries; Sarri's Juve won Serie A, Pirlo's Juve is (currently) in fifth place.
Tonight Juve plays against Sassuolo. Next game is against Inter. Last game is against Bologna. Juventus has to win all three games to hope for a Champions League spot. Will they make it?