The German media were quick to paint a picture of Mr Liener as an isolated outcast who was banished from the company he served for 28 years after an amazing public and highly personal attack in July on his former boss, Edzard Reuter.
Mr Liener's outburst, contained in excerpts from a 76-page document which appeared in a German business magazine, cost him his remaining positions at Daimler, including lucrative consultancy work.
Mr Liener, who is credited with masterminding Daimler's US share listing in 1993, was apparently piqued at having to step down as finance director in May at the same time as Mr Reuter, the former chairman, who was four years his elder.
But sources close to Daimler-Benz insist that Mr Liener was not cold- shouldered by the company after the spat with Mr Reuter. They even suggest that the close personal relationships he enjoyed with several senior Daimler managers, including new chief executive, Jurgen Schrempp, had been improving right up until his tragic death.
Although no longer on Daimler's pay-roll, Mr Liener continued to play an active role in some of Daimler's investments. For example, he remained on the board of Fokker, the ailing Dutch aircraft subsidiary, until last week when he was replaced by Daimler's new finance director, Manfred Gentz.
What then drove Mr Liener to hang himself? The most plausible explanation comes from the Stuttgarter Zeitung, a respected local German newspaper. It suggests that Mr Liener could not face the prospect of personal bankruptcy arising from a failed property venture.
Like many other west German investors, Mr Liener was lured by the carrot of huge tax breaks to invest in real estate in east Germany. But his partner in the project soon ran into financial problems, while the properties they bought in Berlin proved difficult to let. That left Mr Liener saddled with massive debts.
For someone who spent most of his time at Daimler travelling around the world in the company's Lear jet, acting as a sort of unofficial ambassador for German business, the idea of such a personal failure was too much to bear.
Mr Liener's suicide completes a miserable year for Daimler-Benz. In the summer, Mr Schrempp was arrested in Rome with two colleagues after an early morning fracas involving the local carabinieri.
And in September, Daimler stunned the stock market when it blamed a strong German mark and massive provisions at its aerospace arm, Dasa, for a worse than expected first-half net loss of almost DM1.6bn.
The losses were an indictment of Daimler's over-ambitious attempt in the late 1980s to become an integrated technology group, taking in everything from aircraft and missiles to satellites and trains, on the back of the highly profitable Mercedes-Benz car and truck activities.