Every minute your servers are down is a minute that people cannot buy your products. Amazon and Google have determined that page load delays of only fractions of a second result in significant loss of revenue: on Amazon, a 100 microsecond delay in load time resulted in a 1% decrease in sales. For Google, the difference between a 10-result page which loads in 0.4 seconds, and a 30-result page which loads in 0.9 seconds (a mere half second difference) decreased traffic and ad revenues by 20%. The bottom line is that web-users are impatient.