"It took four years for Airbnb to serve its first 4 million guests — a number which has grown to 9 million in the nine months since the end of last year. In the time since CEO Brian Chesky spoke at YC’s Startup School in 2010, the service has grown more than 73x, according to Blecharczyk."Trecho retirado de "Airbnb Has Now Served 9M Guests Since Being Founded, Up From 4M At The End Of Last Year"
BTW, dois conselhos funadamentais:
" try to serve a few users that love their product, rather than many who just like it.
“do things that don’t scale.”"