It’s not like Beyoncé wants to be “really mean,” in the words of her mom, Tina Knowles —she just wants her show to run like clockwork.

Apparently backstage at shows—a la the Renaissance World Tour, which closed a month ago—Beyoncé “can cop a mean attitude when she’s in the midst of super-fast costume changes during her concerts,” Page Six reports.

Beyonce performing at the Renaissance World Tour
“We laughed about this recently because I was saying, ‘Girl, you get really mean back there,’ and I am really happy that I don’t have to be back there anymore,” Knowles said on yesterday’s episode of Sherri. “We’d laugh because she used to do ‘Flaws and All.’ She would say, ‘I’m a b— in the morning,’ and I’ll be like, ‘And the evening, too!’”

That said, Knowles said her daughter is aware that she can get out of line, and always apologizes afterwards. “She’ll be like, ‘Mama, I’m so sorry,’ and I’m like, ‘I know,’” Knowles said. “Sometimes she’ll be crying, and I was like, ‘She’s crying because she know she just said some crazy stuff to us,’” she added, laughing.

Beyonce performing at the Renaissance World Tour

Beyonce at the Renaissance World Tour

Beyonce at the Renaissance World Tour
The stress isn’t for no reason backstage at a huge production like the Renaissance World Tour: “But that’s the heat of the moment, because you’re trying to get your shoes on, and everybody’s waiting, and if somebody’s messing up or they lose the shoes, then you messed up the whole show,” Knowles said. “So, I understand it.”

The RWT featured more than 600 costumes, Knowles said, and “she still has maybe 150 costumes that she hasn’t worn,” she added. “But every night she did at least four to five new costumes.”

Beyonce performing on her Renaissance World Tour in East Rutherford, New Jersey

Beyonce and Meghan Markle at The Lion King premiere

Beyonce at the Renaissance World Tour
The tour broke records as the highest-grossing tour by a female artist in history and earned an incredible $579 million, Entertainment Weekly reports. If you missed it while it was on the road, you can catch it in theaters, when the Beyoncé-directed Renaissance: A Film by Beyoncé comes out December 1—one month from today.