[michaelt]

> Oversubscription is not gambling.

Sure it is.

If I promise 30 people they can have a burger at my barbecue, but I only buy 20 burgers, I'm gambling that 20 people or fewer will show up.

It might be a reasonable gamble, based on past barbecues - but the guests left hungry will still be hungry, and I'll have broken my promise to them.

[kalenx]

That's not the same thing. A more adequate comparison would be to say that you promised 30 people they can have a burger, but can only produce 5 burgers per minute. If everyone show up at exactly the same time, you won't be able to satisfy them all (they'll have to wait). But overall you can consider that the probability of such thing happening is small enough to take the "gamble".

[Hikikomori]

It might be if traffic had sudden jumps of like 30%, but it doesn't and there is headroom available. Traffic increases slowly over time and you have plenty of time to upgrade your network.