It's fair to say most celebrities wouldn't recognise when they're in the midst of creating albums or TV shows that would one day be seen as iconic pop culture.
While that is the truth, it'd be fair to assume those celebrities, if questioned, could easily explain what went into creating those icons later in life.
For some celebs though, when it comes to recounting those iconic moments there's a few that'll just stare blankly back.
These are the times celebs were too out of it to remember what they did.
Matthew Perry on Friends
Forever regarded as one of the greatest shows of all-time, Perry revealed to BBC Radio there's a large part of the show he doesn't even remember shooting.
While chatting to Chris Evans in January of this year, the Friends star said he was often "a little bit out of it" when filming and admitted he can barely remember seasons three to six (1996-1999) due to his addiction to alcohol and drugs.
The 47-year old is now sober and a celebrity spokesman for the National Association of Drug Court Professionals.
Colin Farrell on Miami Vice
The sleek remake of the same-name TV show might've received popular reviews but one actor who doesn't mind either way is Colin Farrell.
In a 2010 interview with Hot Press Magazine, Farrell said "I've seen bits of it since and I just stare blankly at them."
"I don't remember any of it. At least that's my excuse for all the people who thought it was s***e," he added.
The actor starred alongside Jamie Foxx in the 2006 detective crime film but admitted he was so addicted to drugs he jumped on a plane to rehab as soon as the movie wrapped.
Carrie Fisher on Star Wars: The Empire Strikes Back
Fisher revealed her drug habits were at their peak while filming the second instalment of Star Wars: The Empire Strikes Back.
While in Sydney to promote her autobiography Wishful Drinking back in 2010, the actress admitted they did cocaine on "the set of the ice planet."
"I didn't even like coke that much. It was just a case of getting on whatever train I needed to take to get high," she added.
In that same year, Fisher joined her then boyfriend Dan Aykroyd and John Belushi to star in the Blues Brothers where cocaine was actually written into the budget to keep the crew awake.
Director John Landis also described finding a "mountain of cocaine" in Belushi's trailer one day whose erratic behaviour became so bad the crew had to conspire to keep drugs away from the actor.
Belushi passed away less than two years later from cocaine and heroin abuse.
Alice Cooper on the 1980s
If you've recorded close to 30 albums over your career you'd be forgiven for forgetting one or two of them but in 2009, Cooper revealed to The Quietus he pretty much blacked out from the years 1981-86.
The original shock rocker told the publication he drank too much in the 80s which made him forget he'd recorded, and subsequently toured, albums Special Forces, Zipper Catches Skim and DaDa.
"I would actually like to go back and re-record those three albums because I never really gave them their due. I love the songs - I just don't remember writing them," he said.
Ozzy Osbourne on the 1990s
When Osbourne revealed he genuinely couldn't remember most of the 1990s due to being "loaded all the time" most people weren't that surprised.
The Black Sabbath singer was actually kicked out of the band in 1979 after his band mates became fed up with his drink and drug fuelled behaviour.
The 68-year old's black out period came more than ten years after that which he revealed in a 2014 interview with Q Magazine.
"I don't really remember the '90s. I don't know why. My drug addiction and alcohol addiction were absolutely fierce then. I was just going for it full bore, so there was a lot of blackout time," he explained.
That means Osbourne didn't remember his album No More Tears, the Grammy award winning Live & Loud and the double platinum selling Ozzmosis.
David Bowie recording Station to Station
Cocaine and the forgetfulness it causes strikes again as David Bowie revealed back in 2011 he has close to no recollection of recording his 1976 album Station to Station.
Bowie told his biographer Nicholas Pegg all he remembered was "blurting out guitar instructions" at one point but his self-described "soulmate" cocaine stopped him from remembering much else.
Musician Tony Visconti recalled a night he, Bowie and John Lennon hit the town.
"We did mountains of cocaine, it looked like the Matterhorn, obscenely big,
and four open bottles of cognac."
The legendary Bowie passed away in January after an 18 month battle with cancer.
Stephen King on writing Cujo
While plenty of authors turn to varying methods and substances for inspiration, King turned to "a case of sixteen-ounce tallboys a night" during a period of his career.
Already a hugely successful author with books Carrie and The Shining under his belt, King was at such a respected level he could basically write anything he wanted.
Having written more than 60 books throughout his career it was his 2000 memoir On Writing that revealed the extent of his partying ways in the 1980s where he admitted his extended drug and alcohol binge caused him to forget most of the decade.
Kendall Jenner getting gifted a Rolls Royce
Far from creating an iconic piece of pop culture, this one is still worth a mention because who could actually forget being given a free Rolls Royce.
Khloe Kardashian appeared on Jimmy Kimmel Liveto reveal "some prince" gifted young Kendall Jenner a Rolls Royce for her 21st.
When Khloe excitedly asked Jenner the next day how she got her gift worth hundreds of thousands of dollars home, Kendall replied "Oh my god, I forgot a car last night"
"That's how drunk she was," said Khloe.