It came not with a bang but a whimper. James Levine, the conductor who led the Metropolitan Opera and its orchestra to new heights of excellence; who did so much to keep vivid the works of Verdi, reanimate Berg, and add languorous length to Wagner; who worked so closely and so thoughtfully with countless great singers over the course of his 40-year tenure, will retire at the end of this season, according to a press release the Met sent out on Thursday afternoon. And alas, this news will be greeted not with shock but with a chorus of, “If only it hadn’t taken him so long.”

Levine’s brilliant tenure has been overshadowed, in recent years, by a string of health problems that only seemed to be reported after there was no further denying the persistent rumors (not until this season, for instance, has the Met officially conceded that the “benign form of Parkinsonism” he has been suffering from for years is, in fact, Parkinson’s disease). It wasn’t just the illnesses, but the constant alternation between concealment and an excess of revelation that kept so much attention focused on them and away from the music. Taking his boss, Peter Gelb, to his own doctor’s appointment, and having that reported in the New York Times, marked a particular extreme in what in Internet-speak is known as TMI, after months and years of excessive secrecy.

Hanging on too long has had all kinds of consequences. Had Levine left the Met five or ten years ago – say in 2006, when an onstage fall at the end of a performance during his short-lived directorship of the Boston Symphony Orchestra triggered the start of an odyssey of health problems – he would now be remembered mainly as the steward of some of the glory years of America’s leading opera company. Today, however, the Met is struggling with its identity and its box office – sales for some performances are said to be abysmal — and Levine’s often merely nominal tenure in recent years has only compounded the problem by keeping the house more or less musically adrift. He is not only guilty by association; he bears some of the responsibility, particularly since by clinging to power he has not made room for potential successors – like Fabio Luisi, widely seen as having been groomed to take over – fully to establish themselves.

It’s a shame to have tarnished such a fine record. Levine at his best stood for energy, vitality, a fresh approach to tradition mixed with reverence, and a real understanding of voices in a field that desperately needs such understanding but can’t always count on finding it in busy international conductors who don’t always have the time to work with singers, or the knowledge of how to go about it. He has led more than 2,500 performances with the company, a number no one else can touch.

Levine is not by any means going away. He will withdraw from next season’s new production of “Der Rosenkavalier,” but, as music director emeritus, conduct Verdi’s “Nabucco,” Rossini’s “L’Italiana in Algeri,” and Mozart’s “Idomeneo” – all revivals seen at the Met before. He will also continue to lead the Lindemann program, the company’s training program for young artists. And this season, he will finish out his scheduled performances of “Simon Boccanegra” and “Die Entführung aus dem Serail,” as well as leading two of the Met orchestra’s three Carnegie Hall appearances in May. Look forward to a string of performances studded with ovations from a still-adoring crowd. But look forward, too, to the possible emergence of someone with the vision and energy (some are betting on Yannick Nezet-Seguin) to take over and lead the Met to the next rebirth that it so sorely needs.