OK, if you were going to make a list of the biggest celebrities divas out there, fashionista singer Jennifer Lopez might not be the first one to come to mind, but she's right up there with the likes of Mariah Carey and Queen Beyoncé.

It's a combination of things really. It's about the demands she makes, how she treats other people, and her egotistical opinion of herself. Well, reportedly, Jennifer Lopez makes outrageous demands, treats most people like dirt, and thinks she is the greatest singer and actress in the world.

Now, that means that her staff has it tough. And pity anybody like a maid or airline attendant that comes within her orbit. And her fellow co-stars? She spends most of her time dissing them personally and professionally. And, trust us, they return the compliment, saying she is difficult, if not impossible to work with. And we haven't even gotten to the diva demands yet.

Let's have a look at why no one wants to work with or for Jenny from the Block, a.k.a. the still hot Jennifer Lopez

The Servant Class

Whether you are a member of her staff, a workman at her house, an airline attendant, or a maid, JLo is going to ignore you.

Workmen at her house have complained that she won't even acknowledge them or look them in the eye. It's as if they are not there.

Take the United Airlines First Class airline attendant who merely asked JLo what she would like to drink.

"I just said, 'What can I get you to drink?' But Jennifer refused to even acknowledge me. She turned her head away and told her personal assistant, 'Please tell him I'd like a Diet Coke and lime.' " JLo refused to even look at him. The assistant did as she was told.

It gets a lot worse when you look at the German hotel maid who dared to knock on Jennifer's door and politely ask for an autograph.

Pray Dodaj, a maid at a luxury hotel in Dusseldorf was a big fan of Jenny from the Block.

She said: "I am an incredibly big fan so I took all my courage and rang the bell to get an autograph, but I was rejected by two assistants at the door. "

She continued: "A day later the cleaning company that employed me . . . called and said that Ms. Lopez had complained. I was fired right there on the phone."

Apparently, the humble act in 2002's Maid in Manhatten wasn't for real!

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Want to be on her staff? Be prepared to be on call 24/7 to cater to her every whim and need. And, unless you are one or two of the staff who are very senior, don't even expect her to acknowledge you. One staff member said it was like working for a ghost.

Her Co-Stars Are Routinely Dissed (And Clap Back)

JLo has gone on record saying she is a great actress. Some would disagree.

So, what does she think of Cameron Diaz? Jennifer dismissed her saying she was: "A lucky model who's been given a lot of opportunities. I just wish she would have done more with them."

Cameron, in turn, has commented on JLo's behavior on the set of 2012's What to Expect When You're Expecting. JLo pretty much ignored Diaz. For her part, Cameron has said that the huge entourage Jennifer insists on bringing along and her tendency to do things like stop in the middle of a scene if she has a meal break scheduled made her difficult, if not impossible, to work with her. She said Lopez should stick to singing, referring to it as her "day job". Ouch.

Now, whatever you think about Gwyneth Paltrow, she is generally considered to be a fine actress. Jennifer's opinion is "Gwyneth who?"

Lopez was scathing when she said: "Tell me what she's been in? I swear to God I don't remember anything she was in. . . I heard more about her and Brad Pitt than I ever heard about her work." Talk about elitist. Being rich and famous has gone straight to Lopez's head.

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Those Diva Demands

Where do we begin? Let's take the Indian Premier League Twenty20 cricket tournament in 2013. Lopez was supposed to appear alongside rapper Pitbull. But when she demanded a private plane and countless hotel rooms for her staff, the organizers said no way. And JLo was out.

RELATED: Jennifer Lopez Is Totally Overrated, According To Howard Stern 

The cricket thing was bad enough. But the demands she made to appear at the World Music Awards in 2010 are in a class of their own. The Mirror reported that JLo's demands included having a helicopter kept on stand-by, as well a "custom-fitted speed boat" and (wait for it) "a pair of diamond-encrusted headphones to drown out the sound of the boat's motor . . ." And she wasn't finished, demanding that she be given an entire floor of the hotel.

We could go on and on. But you probably get the drift. Nobody, but nobody wants to work with or for Jennifer Lopez. We hear even A-Rod is afraid of her!

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