Dov Charney was no one’s idea of a button-down executive.

For years, Mr. Charney, the founder of American Apparel, has stood like a tabloid monument to fashion industry excess, a barely restrained id in a fitted black shirt. The stories about his personal life are legion: the accusations of sexual harassment, suggestive emails, nude photos — the list goes on.

But on Wednesday, the company that Mr. Charney founded in 1998 decided enough was enough. Worried that Mr. Charney had become a liability, the board ousted him from his roles as chairman and chief executive in a coup that leaves American Apparel facing an uncertain future.

“The company has grown a lot bigger than just one person and the liabilities Dov brought to the situation began to far outweigh his strengths,” said Allan Mayer, the board’s new co-chairman. A lawyer representing Mr. Charney did not return telephone calls on Thursday.

Exactly what prompted the move was unclear. People with knowledge of the situation said an internal investigation had turned up new details about Mr. Charney’s salacious behavior — only this time, they said, American Apparel could no longer afford the potential cost. Its creditors were growing anxious after years of losses at the company. Even a suggestion of new controversy might frighten stockholders, who have watched their investment plummet in value in recent years.