When she debuted, Lady Gaga proclaimed she was in it for the fame. Five years later, she lives for the applause. Plenty has changed in between.

Now, the star wears couture rather than hot-glued crafts, she dates an actor-model rather than a bar owner, and, despite hoards of superfans, her popularity is beginning to decline.

2013’s “ARTPOP” disappointed in sales compared to previous successes “Born This Way,” “The Fame Monster” and “The Fame.” Boasting early hits and some potential, “ARTPOP” lacks the unity and staying power of Gaga’s earlier efforts. Her image is waning, too — the queen of avant-garde’s sporadic jumps from identity to identity have become underwhelming.

While 2008’s “The Fame” was a promising start to Gaga’s career, 2009’s “The Fame Monster” EP was Gaga’s magnum opus. The period of touring and public appearances between its release and “Born This Way” is something the singer has since struggled to top.

On the Monster Ball tour, the world tour supporting her EP, Gaga showed audiences her performing prowess with colorful ’80s imagery and a “Wizard of Oz”-style narrative. With a big budget and a bigger voice, she concocted just the right formula of kitsch, inspirational speaking and experimental performance.

The Monster Ball also saw the coinage of the term “little monsters” for the star’s devoted fans, and their custom of camping out for weeks preshow to secure front-row spots. With that kind of hype, Gaga reasonably felt pressure to outdo herself on her next album-tour combo.

2011’s “Born This Way” was the next step, and by obsessing over her extravagance, Gaga began to lose the interest of new and casual fans. She even burned herself out, cancelling the majority of American shows due to a hip injury. After a period of recuperation, she returned strong with “Applause.” “ARTPOP” as an album, however, failed to meet the bar set by the first single.

Had Gaga never put out “The Fame Monster,” her subsequent release might not seem so disappointing. She has the pipes, the creativity and the drive but she seems overwhelmed by the pressure to outdo herself — her popularity has suffered as a result.

As for the future, Gaga is planning something literally otherworldly, slated to be the first artist to sing in space. Ground control to major Gaga — maybe something more down-to-earth would be a better next step.

A version of this article appeared in the Thursday, Dec. 5 print edition. Alyssa Buffenstein is a staff writer. Email her at [email protected].