...and yet, TMP wasn't exactly the kind of success that inspired sequels to emulate it, which certainly suggests it was a failure in significant ways regardless of how it fared financially.
ETA- I think this statement from the appropriate Wikipedia article might summarize how TMP fared best: "Released in North America on December 7, 1979, Star Trek: The Motion Picture received mixed reviews from critics, many of whom faulted the film for its lack of action and over-reliance on special effects. The final production cost ballooned to approximately $46 million. The film earned $139 million worldwide, falling short of studio expectations but enough for Paramount to propose a cheaper sequel. Roddenberry was forced out of creative control for Star Trek II: The Wrath of Khan."
If it was in objective terms a financial success, it apparently was not viewed as such by the studio.