Operating at scale is an invaluable experience. If you're designing the status-entry box on Facebook, you're designing something that processes billions of characters of text a day, and has to work for hundreds of millions of users in a variety of use-cases. Pixels at that scale have ramifications in the millions of dollars.

You get paid a fair amount of money, and you get to work on something that all of your friends, family, and colleagues use in their daily lives.

There's a lot of really, really smart people that can mentor you, especially if you're young in the industry.

They're great places to network.

I think any number of the things you mentioned could be true.

For me for example, teaching, learning and networking are huge, but I would also shamelessly leverage the credibility gained through brand association.

I think consumers are particularly susceptible to this brand residue, and tend to think highly of people and products associated with their favorite brands, even from past associations.

Note: This is purely anecdotal.

What made Apple appealing to me is that as a company it shares the same core values that I do. I would've chosen to work at Apple regardless of their prestige, scale, or paycheck.

I don't think I would consider working at Google or Facebook, because those companies have core values that are different from my own - even though they have similar scale, and pay.

While AOL's not on the scale of Apple or Google, it still meant designing for millions of eyes, and there's definitely something about that I was enticed by. And because of the multitude of layoffs every few months it was like a revolving door of talent – as the people I worked with at AOL went on to do other things, they'd oftentimes take you along with them (for freelance, or even hire fulltime). Those relationships were invaluable.

To the point of money..... During a job interview at Netflix we'd gotten to the negotiation stage, and I was told that a salary of $xxx,xxx+ wouldn't be at all unreasonable for someone who'd come from a background that included working for Apple. (Needless to say, Blockbuster doesn't have that kind of umph.)

Personally I'd say it would be the security; you know that your product isn't going to go away any time soon.

Some of the best people work there, and you wanna work with and learn from the best people.

For me personally, I'd love the opportunity to work on something that millions of people use every day.

Even if you work on a small section of that platform, it's still going to get a lot of eyeballs.

The slight change can result in huge increase (or decrease) of actions, that's an amazing thought. I love the thought of that.

Imagine changing something on Twitter that increased signup conversions by xx%

Also, the people that work at Facebook/Twitter, always seem to gravitate to the next big/interesting thing. They either move from big tech company to big tech company or get poached for awesome startups.

I bet they are surrounded by amazing people all day long who occasionally leave to start their own thing and take staff with them.

You'll probably always be able to get your foot in the door of whatever SV company had positions available with those guys on your CV

$$$$$$$$$$$$$$$

Curiosity; because you'll never know what it's like to work with such a big, notable company until you do. You may end up not liking it, but at least you figured that out and tried. It's at the opposite end (in a way) from being your own boss or starting your own start-up. To be honest, I don't know if I'd like all aspects of that career-path either, but I might give it a try some day. Why not?

to put it on your resume.

The largest company that I worked in was myspace back when I did my internship. It wasn't the same scale of FB, Google, and Apple but there were still massive traffic going through when I was there. There were some pretty interesting projects to work on and learning from the people there was a massive help in jump starting my career.

Try asking yourself, why would you want to work there? and why not?

I think in addition to all of these, the stakes are pretty high - when you're dealing with such an incredible number of users, you tend to weigh your decisions much more carefully, and learn to spend a lot of times poking holes in your thinking. It's one thing for a small startup site to go down for a few hours, it's another when Gmail or Facebook have to deal with a crisis - millions of people are affected. This imposes a lot of humility and discipline in your craft.

Work culture?