with Elon and you get that opportunity to talk to Elon,

you need to be concise, quick.

- There's definitely 2:00 AM texts

and 6:00 AM conference calls.

- When I used to go into meetings with him,

I used to always stop by our barista

and I would get a couple espressos and chug that down

and then go into the meeting.

- He has never said this, but I've watched it.

You have 30 seconds to make your point.

- [Narrator] Elon Musk is known

by his employees to be intense.

When he took over Tesla in 2008,

he sent the company into crisis mode to jumpstart his vision

of how to reinvent the auto industry.

Now he appears to be using

a similar management playbook to remake Twitter.

We spoke with former Tesla and SpaceX employees

to better understand how Musk became known

for his cutthroat and tireless management style

and what that may mean for his future employees.

(audience cheers)

Step one for Musk is to rally employees

around a lofty company mission.

(tool bangs and whirs)

It's exactly what inspired Carl Medlock

to join Tesla in 2009.

- We were all so excited about the brand.

I mean, we were all working 80, 100 hours a week.

We kinda lost track of our families, our passions

our hobbies, and all that stuff,

but we loved what we were doing.

I never once had Elon or saw Elon do

a rah-rah meeting like that.

- [Narrator] Medlock now runs

his own electric vehicle repair shop in Seattle.

He said he was terminated from Tesla in 2013

over a misunderstanding with his direct manager.

Garrett Reisman was similarly inspired

by the mission of SpaceX and joined in 2011.

- It's a very demanding environment,

but by and large it's not because of him cracking the whip.

You know, making human life multi-planetary,

getting to Mars, having a colony on Mars.

It's something that motivates

pretty much everybody there at SpaceX.

- [Narrator] Reisman left SpaceX in 2018

to teach astronautical engineering

at the University of Southern California.

He said that after seven years at SpaceX,

he wanted to work somewhere less intense.

Yet at Twitter, the mission isn't exactly saving the world.

- They are talking about protecting free speech,

which of course is important,

but it is not as dramatic as trying to go to Mars.

- [Narrator] Tim Higgins is a tech and automotive reporter

for the "Wall Street Journal" and author of "Power Play,"

a book that traces the rise of Tesla and Elon Musk.

- Well, the challenge that Elon is going to have

at Twitter is what are the stakes?

- [Narrator] Neither Elon Musk nor Twitter

responded to requests for comment.

The company's mission is what Musk hopes

will drive people to be hardcore,

a term he uses to describe working long hours

at high intensity.

- You just have to put in, you know,

80 hour, 80 to 100 hour weeks, every week.

- I would see people at 2:00 in the morning

'cause we had finished up an event

and we were all still energized

'cause we were having such a good time.

- [Narrator] And Musk has used this idea of hardcore

to rally his team over the years

as they approach hard challenges.

For example, in 2012, when Tesla was preparing to ramp up

production of the Model S luxury sedan,

Musk sent his team an email

with the subject line, "Ultra hardcore,"

telling them to prepare for a level of intensity

that most of them had never experienced before.

About three weeks after taking over at Twitter,

Musk sent a similar email,

but hundreds of employees opted to leave the company

rather than sign up for Musk's vision of Twitter 2.0.

- The challenge here is Elon has inherited a huge workforce,

and he has to convince them to be on Team Elon.

And we're seeing him try to go through those ranks of people

to find the talent that he's going to need

to pivot the company to a private Twitter, and it's messy.

- [Narrator] Musk himself leads by hardcore example.

- I sleep on the couch over there.

Last time I was here I actually slept, literally,

on the floor 'cause the couch was too narrow.

- I showed up at work early one day,

and it was just me and him and one security guy

in the entire 5.5 million square feet.

And I didn't know he was there, right?

And at the factory,

there's walkways and safety areas and stuff like that.

But when nobody's there,

I just got on a bicycle, riding around,

and here Elon is asleep on this engineer's desk.

- [Narrator] In November, Musk tweeted that he was sleeping

at Twitter's offices in San Francisco.

And it's not just his time, but his money.

- How much did you put into this company?

- (exhales sharply) Oh, man, about $55 million.

- In 2008, when Tesla was at its darkest moment

and he put in his personal last millions of dollars

to fund it, he was even, you know, couch surfing

in Menlo Park and paying my business expenses

with personal credit card debt, right?

His approach is to do anything required

to keep his businesses competitive,

and he lived that every single day when I worked for him.

- [Narrator] Konrad left Tesla in 2011

for Renault Nissan Mitsubishi.

- People that I've talked to with Elon

talk about how he in one hand is incredibly inspiring,

but on the other hand a lot of people will say

he was also exhausting and mercurial,

and after a while they just couldn't keep up with him.

- [Narrator] There is also a history of employees

at Tesla and SpaceX alleging misconduct at the companies.

Musk is also known to quickly make his companies leaner.

When he became CEO of Tesla,

he cut about 20% of the workforce.

About a week after he took over Twitter,

Musk laid off roughly 50% of the staff

according to a document seen by "The Journal."

And people familiar with the matter estimated

that likely over 1000 have resigned.

Former employees have said

that this cutthroat approach instills in them this feeling

that anyone working for Musk is the best of the best.

- Back in the day at Tesla, Elon would often say

that people who work for him are special forces.

- He wants to hire a key engineer who in his mind

has way more value than, say, a hundred engineers,

and to deploy those top talent on the hardest problems,

and be able to move faster

and not have the same kind of level of bureaucracy.

- [Narrator] Former employees have said

that Musk avoids traditional corporate hierarchy.

- If Elon was interested in something you were doing,

he would come and talk directly to you.

He's not gonna go through a bunch of different layers

of management and have the information filter up.

- [Narrator] Musk also motivates employees to work harder

by raising the financial stakes.

- When Elon became CEO of Tesla,

the economy was in shambles.

It was the Great Recession and there was huge questions

about whether people were gonna wanna buy a luxury car,

and not just a luxury car, a luxury car that was electric.

(car door slams)

Similarities to Twitter today,

we've got an uncertain economy.

The company needs to start generating more money.

It has a huge debt load.

It has to find its place in this social media world

that's under a lot of pressure

as the ad market, it kind of contracts.

- [Narrator] In November,

Musk wrote in an email to Twitter employees

that without significant subscription revenue

there is a good chance Twitter will not survive

the upcoming economic downturn.

Musk is still in the early stages of setting up his strategy