Earlier quoted context omitted.
Bingo. Valuations should be based on.... drumroll profits and retained value - EBITDA. When we started basing valuations on arbitrary "well if facebook are $100bn, X must be $y", we set sail for another glorious future of people losing their shirts. Frankly, it just pisses me off - we're a profitable business which has grown 150% YOY for 6 years, and our value is barely £3M, based on our profits and growth. Why an in…
Valuations are based on what someone else might pay - and they might pay a few billion for Pinterest.
In a bubble (tulips, houses, stock markets) there seems to be an unending supply of greater fools, until all of a sudden there isn't, and someone (who of course expected to find some other fool to sell to) is left picking up the tab for assets which are now close to worthless.
If your valuations are based on what someone else might pay in future, you are speculating, and will be lucky if you manage to get out before other people realise the assets you have bought are not worth $1B or whatever you paid for them. If on the other hand you bought because there is a steady income stream from an investment which will eventually pay off the investment and add returns, and thus underpins the price, you don't have to worry about whether this is a bubble or not.