After being disgracefully fired for cheating from his billion-dollar startup, penniless maverick joins his ex-girlfriend’s bankrupt company to regain his lost glory

I assumed it was an extramarital affair. If it is a corporate crime - maybe use a more specific word. Insider trading - money laundering - embezzlement

The logline is tagged as a "Coming of Age" genre. How does it qualify as a coming of age story? How old is he?

"To regain his lost glory": Why will an audience empathize with and root for a character who seeks to re-inflate his own sense of himself? Suggest the story be framed as a redemption story -- not as an ego salvage operation.

Whatever, loglines are about plots, and plots are about the pursuit of a specific objective goal, not the satisfaction of a subjective need. Rocky Balboa does not accept the challenge to fight the champ so he can "find his center". Whatever he discovers about himself is an unintended, collateral consequence of his pursuit of the objective goal, to fight the champ.

So what is your protagonist's objective goal? He joins his ex's business -- then what? What is his *specific* business plan for rescuing the business?

Thank you for the clarification. I understand your story better now. I the logline you only include the essentials because you only have 35 words max to tell your story. Beyond that, people will lose interest.

Here is my rough rewrite which includes the essential elements: main character, major event, the dramatic need of the main character and the obstacles that may prevent him from achieving his goal.

"When a maverick billionnaire entrepreneur becomes penniless for his unscrupoulous dealings, he is driven to turn around a near-bankrupt company hoping to reverse his fortune but is facing management's hostility against his business ethics." (34 words)