[wutbrodo]

> who sets these expectation numbers, how do they get it and why can't normal investors arrive at the same numbers?

I'm not quite sure what you're asking here: "Normal" investors can and do set these numbers. Every time you buy or sell a share of stock at a given price, you're adding your (tiny) signal of what you think the price should be (and nudging it a little in that direction as well). The price of the stock reflects the aggregate of the millions of these little guesses.