> And even if you have to reboot, how long does it take? A minute? How much does that minute downtime cost? It can cost a lot and for that case you have HA. HA

> And even if you have to reboot, how long does it take? A minute? How much does that minute downtime cost? It can cost a lot and for that case you have HA. HA shouldn't mean "we deploy a few times a day which drops our uptime to three minutes so we have to spend a lot". One redundant server and a load balancer is hardly HA and increases costs by tens of dollars a month. And frankly, a minute of downtime is the optimistic case. It all goes to hell when you have a failed software deploy that needs to be rolled back. Or when the application server has a bug that causes crashes and needs to restart every few hours. A single-server setup is only useful for companies where the technology matters far less than the service being provided. If you can tolerate an uptime of only 2-3 nines, great, but that's absolutely not reasonable for companies where the technology is the service. It's not rocket science that paying customers are going to be pissed if your site is unreliable.