[gfaremil]

I think the problem for engineers working for certain companies such as Google, Twitter, or Facebook is not that your customer are advertising companies.

The real challenge (and problem) for some engineers is that your user is not your customer.

The joy of interacting with customers which are actually paying for things you made for them is sometimes priceless.

Also when working for Google, Twitter, or Facebook you might never learn how to envision and build the product (and company from it) which is sold directly to the customer.

So don't expect the next Oracle, Informatica, or Apple coming from ex-Googlers (even they have a lot of engineering knowledge in that space).